US1827695A - Composite gem and jewel - Google Patents

Description

Oct. 13, 1931. H. H. WELCH COMPOSITE GEM AND JEWEL Original Filed Aug. 22, 1924 Patented Oct. 13, T931 UNITED STATES PATENT OFFICE COMPOSITE GEM AND JEWEL Original application filed August 22, 1924, Serial No. 733,472. Divided and this application filed November 25, 1925. Serial No. 71,312.

This case is a division of my application Serial No. 733,472, filed 22 August 1924.

This invention relates to composite real gems, and to jewelry comprising such gems combined with settings therefor, the same involving improvements upon the artificial composite gem of the general type disclosed in my prior Patent 1,421,329, dated 27 June 1922.

lVhile the invention of my prior patent established a new art, the object of the present invention is to improve the construction of my gem in the respects described fully hereinafter with the View particularly of improving its appearance and producing a high grade of composite real gem and ewel of a nature to compete with the ordinary real gem of the prior art used as an article of jewelry for wear on the person, more particularly of women.

The invention consists of the construction described herein and illustrated in the drawings, whereby there is provided a composite real gem which is less fragile and more beautiful than prior gems.

The drawings are approximately of double scale in order more clearly to illustrate the construction.

Fig. 1 is a section of a form of the composite gem hereof, and Fig. 2 is a. section of a modified form of such gem fixed in a setting and the two constituting a jewel embodying my composite gem.

The improvements hereof are directed chiefly to the appearance of my composite gem and the jewels comprising it, although said improvements relate to mechanical features concerning the gem itself and including the strength thereof, and to the cooperation with the gem of the jewel setting therefor in respect of producing the most attractive appearance of the composite gem itself.

In my gem as improved over that of my said prior patent. the attractiveness in ap pearance is materially enhanced, the mechanical setting of the gem is improved. the fragility as compared with prior real gems is very greatly reduced, and means and methods are provided for producing high-grade jewelry at very low cost.

The disclosure of my prior patent related more particularly to the cheaper grades of jewelry, including imitation gems or pieces of shining gold or silver leaves, although a unitary real gem (not composite) was shown loose in a larger glass container; but the present invention relates more particularly to high-grade jewelry with composite real gems, a special object being to provide, at lower cost than prior natural gems, a composite real gem as an element of a high-grade jewel which has greater attractiveness than prior high-grade jewels comprising unitary natural gems, so that my jewelry of greater attractiveness can be. sold at a lower price than high-grade gcmjewelry heretofore.

In the present invention, I prefer usually to employ the valuable feature of my said prior patent consisting of the mobility of display elements due to the loose housing thereof in a hollow body, container or housing having walls of suflicient transparency to show the changing hues of the mobile display elements. hit in the attempts to produce the results now embodied in the present composite r-al gem, i. e., a low-cost gem or composite opal of superior attractiveness and tastefulness, of low fragility, (and whether or not embodying the characteristic feature of mobility of loosely housed display elements), various problems were encountered of which the practical solution will be sufficiently clear from the following to enable workers in this new art to make and use the invention.

In the first place, the improved gem or composite opal hereof in general appearance resembles an ordinary and usual lJl'(('l(lll. gem in a customary jewel setting, as attempted inadequately to be indicated in Fig. 1. my composite real gem or opal being in general of the same order of size as prior real gems as ordinarily employed in womens jewelry, and in good and refined taste adapted for competitive sale with the prior real unitary gems. But to that end. several items are requisite. First, my composite real gem includes a hollow body or housing of glass or the like for retaining the small real gems or opal fracture fragments to be described, and

this housing resembles in external configuration and size the general shape and size of of unitary real gems as heretofore used in jewelry. But, in order to further effect general resemblance between my composite real gem or opal and the prior unitary gems (irrespective of the mobility of the fracture parts of the former), the mobile housed display elements in the present invention consist of small fragments (as fracture fragments) of real gems particularly opals (so as to constitute a composite natural gem or opal with independently mobile parts) and not merely any kind of fragments or small gems, but preferably quite small or minute fracture fragments of opals, although each in volume sufficiently large to contribute to the production of the reflected light effects to be described, and of considerable number in proportion to the volume of space inside the transparent housing, such that substantially the entire interior space of the housing which is exposed to the eyes of the observer, may appear to be substantially a unitary natural gem or opal with characteristic beautiful color effects of reflected light from the reflecting surfaces of the small opal fragments. Also, in order further to effect general simulation between my composite gem or opal and prior unitary gems in general (irrespective of mobility of the parts), the housing preferably is quite transparent, colorless, and of such shape and thickness of wall that, in combination with the particular small opal fracture fragments housed therein, the effect will be that light rays passing through such glass housing and through the liquid to be described and incident on or into the contained small opal fragments and reflected to the eyes of the observer, (particularly when liquids to be described are employed), may act on the eyes as if no housing were present as if the observer were looking directly at a unitary opal (save for the changing colors of the moving fragments), and so as to prevent any impression upon the observer of the existence of any such hollow transparent housing and contained group of small gems as things separate from one another, but so as to effect the impression (as indicated in Fig. 1) of vision of a natural gem having a size and an external shape generally corresponding to the size and external shape of prior unitary gems without any such housing.

Figs. 1 and 2 show my more or less globular composite real gem embedded in a setting to constitute a jewel which as a whole is adapted for wear as a pendant, this composite opal itself, irrespective of "the particular setting, being adapted for personal wear as earrings, breast pendants or the like.

A portion of the globular glass housing or container is shown at 14, Figs. 1 and 2.

Housed in container 14 is a group of small display elements 199 which as shown consist of quite small fragments which have been broken off from relatively large opals such as 19 of my said prior patent. I have discovered that if any such ordinary opal be broken up into fracture fragments of such general small siZc as the crumpled or wrinkled glittering or scintillating pieces of gold or silver leaf 16 of Fig. 2 of my said patent, (i. e., irregular fracture fragments having a general average diameter of about one-eighth inch), then the resulting small fracture opal fragments will possess such reflecting surfaces that when a substantial number of such fragments indicated in Figs. 1 and 2 hereof) are immersed in some such viscous liquid as glycerin the vari-color reflections thru the colorless liquid and colorless housing from each of the individual fragments are at least as beautiful as the reflection from the parts of the surfaces of a complete unitary large natural opal, notwithstanding the seeming destruction of the opal gem by such breaking up; and I have found that the many additional reflection surfaces and reflections resulting from such large number of opal fragments separated from one another by diffusion upon the motion thru the liquid, rovide a much more striking and beautiful e ect than the original natural large unbroken opal, the whole composite gem presenting a very much more richly beautiful effect indeed than the comparatively cheap-looking merely glistening, twinkling or shining metallics of the trade of my said prior patent, the multitude of separate opal fracture fragments here very slowly moving thru the liquid and separated and spaced from one another by the liquid in fact having the rich and colorful appearance of an unbroken natural opal, but in greater degree, and the new composite gem being in fact a real opal altho in a. modified improved composite form with the advantage of increased color variegation resulting from the slow movement of the many reflecting surfaces each of multi-colors of the variousdiffused and separated opal fracture fragments. the whole presenting to the eye substantially the appearance (see Fig. 1) of a unitary gem of the size and the external shape of the colorless transparent housing, and masking the existence of the latter as a separate thing. This latter effect (of a size of gem the same as that of the housing) is produced notwithstanding the slight, slow movement of the fracture fragments through the liquid and notwithstanding the substantial thickness of the wall of the glass housing,

which (Fig. 2) is of the order of three thirtyseconds of an inch, more or less, in order to impart greater strength of resistance to exterior impact than that possessed by the ordinary unhoused unitary gem or opal.

This effect of over-all resemblance of my glass-housed composite gem to a unitary gem of the same general size and shape as the housing is due to the fact that the rays of light, coming to the eye from the multitude of housed small gems, are refracted as they pass through the glass housing and the atmosphere to the eye, causing the small opal fragments next the interior housing-wall to be displaced in appearance or effect so that they appear to extend to the outer surface of the gross structure, contrary to the fact that they lie a substantial fraction of an inch inwardly of such location. Further optical features will be described later. Also, and preferably I provide sufficient looseness of the plurality of small housed gems 199 to permit their mobility as independently acting units resulting 'from movement of the composite gem as a whole, by leaving, wlthin the lower globular portion 14 space which is not occupied by the minute units. This gemfree space is indicated at 15 which indicates the preferable employment at 15 of a liquid such as glycerin it being assumed in the drawings that the entire composite opal 1s in motion, which is usually the case when on the wearers body so that the opal fragments 199 freely move about in housing 14. This opal free space 15 may be larger or smaller than is shown especially under the following circumstances. As may be understood clearly, any large volume of liquid-filled space 15 (i. e. having no gems 199 moving thru it) detracts from the intended appear ance of the composite opal as a unitary real gem of size and shape substantially indentical with the size and shape of globe housing 14; but when the composite opal is worn on the body, the movement of the small fragments 199 (especially when there is employed the preferable liquids to be described), has the effect of tending to cause the appearance of such a unitary gem coincident with the volume of housing 14 including space 15, because the bodily movement of the entire composite gem causes individual movements of the small opal fragments 199 which therefore become more or less separated from one another, resulting in an appearance of greater volume than the gem-filled space when the gems lie in a compact mass, where the opal fragments, at rare occasions of rest when worn on the person, lie in a closelyassembled mass; so that as a result of such movements the visual effect of any opal-free space 15 is altered, and any large volume of it is reduced so as to reduce eflect of contrast with the minimum gem-filled space of Fig. 2; and this without such great increase of separation of the gem-fragments from one another as to detract from the appearance of the entire group of small gems as a unitary gem. Now, if gem-free liquid filled space 15 be sufficiently small (while large enough to permit the preferably slow and slightly individual movements of the small gems, very slowly milling around and interweaving), then in use, and with the small gems in motion, and the individual members 199 of the entire group separated from one another and diffused more or less throughout the entire space in housing 1 1, there will be no substantial appearance of a gem-free space detracting from the unitary appearance of the gem by permitting a view of the liquidfilled space 15 of housing 14 not apparently filled with small gems.

I much prefer ordinary colorless glycerin as the liquid 15 because (1) glycerin possesses the special property accompanying its high refractive index not only of enhancing the brilliancy of the natural opalescence of the gem, but of enhancing the beauty of the opalescence of the many fracture faces constituting reflecting surfaces of each of the moving fracture fragments themselves considerable in number and moved in the liquid into spaced positions presenting said multitude of opalescent fracture faces to the eyes of the observer; and (2) while the glycerin as a liquid permits such freedom of motion of the opal fragments yet it possesses a viscosity Ineventing a rapid, jerky or intermittent motion of the fragments which would cause a too evident appearance of motion which would detract from the desired general effect of a unitary gem not consisting of separate fracture fragments, such viscosity of the glycerin permitting a slow, gradual and continuous motion of the numerous opal fracture fragments producing minimum effect of motion but a predominating effect of ever-changing opalescence resulting from such comparatively unobservable motion; the numerous opal fragments being more or less diffused by their motion to locations distributed throughout the body of glycerin and thereby permitting vision not only of the moving opalescent fracture faces of the fragments nearest the eye but of many if not all the moving opalescent fracture faces of the fragments in the middle of the housing thereby presenting to the eye the multitude of everchanging opalescent fracture faces of each and all the numerous fracture fragments at times when there is no relative movement of the eye and the gem as a whole, the movements of the fragments thru the liquid being all that is necessary in order to produce said effects; and (3) the glycerin has no deteriorating effect on the opal fracture fragments and (4) the heating of the housing during manufacture of the composite opal does not result in the formation of salts which might affect the transmission of light from the reflecting surfaces of the opal fracture fragments, and (5) the glycerin when used with a housing 14 of pyrex glass (owing to the like high refractive indices of ill) such glass and glycerin) reduces the visibility of the adjacent surfaces of the liquid and the solid glass housing as separate things and thereby assists in producing the effect or illusion of a unitary larger opal thereby cooperating with the slow continuous movement of the numerous fragments in creating such illusion of the existence and the slight slow motion of the many small opal fragments. All the above results are obtained merely by placing in housing 14, Fig. 1, a mixture of the opal fracture fragments 199 and the glycerin 15, the number of fragments being large but insufficient in total volume to fill the housing 14 and leaving a substantial opal-free but glycerin-filled space 15A in said housing; the glycerin 15 itself being sufficient in volume to fill housing 14 completely and extend into the smaller housing 0 portion 144 for the important purpose to be described.

Other liquids than glycerine are far less desirable with opals because they cause far less beautiful color effects from the composite opal, the object of this invention being generally directed to a structure producing the most beautiful effects so as to be superior to prior unitary opals in appearance as well as in reduced fragility. But other colorless transparent liquids may be used, including an aqueous solution of borotungstate of cadmium, which by the water of solution readily may be made to have substantially the same density as the opal fragments and therefore acts as a suspender of the latter so that they may not sink to the bottom but tend, irrespective of movements of theminute opal portions of the composite gem, to be separated from one another for an effect to be described. Also other liquids or mixtures of liquids may be employed. But it is not necessary to have any particular relation of density between the gem-fragments and the liquids, i. e., it is not necessary that when the composite gem is in a position of rest the small opals should remain suspended in the liquid; for all the desired color effects can be obtained by such structures as Figs. 1-2 above described, when the individual small opals are set in motion, using glycerine as liquid 15, notwithstanding that the group of small opals, when the compos te gem is in a position of rest, may sink away from the top of housing 14. Even in that position (which is abnormal while the 'ewel is being worn), the glycerine surrounds the individual small opals and enhances their brilliancy due to its high refractive index.

The further effect of viscous liquid 15 and the opal-free space Figs. 1 and 2, is to permit diffusion and separation from one another of the fracture fragments 199 so as to expose to the eye all the opalescent fracture faces of each and all the many moving separate fragments all as distinguished from a 65 view of a compact group of such fragments which produces little better effect than a view of a natural complete unbroken opal viewed thru the same liquid. Thus in Figs. 1-2 those of the opal fragments 199 which lie in the center of the diflused group, i. e., in the'center of the space in housing 14, are caused to have the opalescent fracture faces of each and all of them exposed to the eye as they slowly move and turn and weave about in spaced relations to one another, all as contrasted with the inferior effect from a view of the exterior surface of a natural unbroken opal of the same size as the new composite opal.

The increased opalescent effect of the invention as compared with a large natural unbroken opal which effect results from the freedom of the many small opal fracture fragments to move severally and independently of one another thru the liquid is enhanced further by the lens curvature of the internal wall of the pyrex glass housing 14 which lens magnifiesthe small opal fragments and concentrates the light as a spotlight incident on the central portion of the housing space so as to bring out the opalcscent effects to the eye from the various fracture faces of the central opal fragments in the midst. of the group diffused in the liquid, this being in addition to similar effects from those fragments which are moving closer to the interior wall of the housing 14, said effect from the fracture faces of the central fragments being visible thru the spaces betweenthe outer fragments of the diffused group; and all such effects resulting from the separated opal fragments even if none of them be in motion as in the liquid, the colors changing upon slight relative motion of the eye and the composite gem as a whole.

My composite real gem is shown in Fig. 2 105 in a jewel consisting of a finger ring 122 wherein only a portion of part 14 of the housing is exposed from the setting.

In further perfecting the invention as shown in my said prior patent, and in connection with the employment of the'multiplicity of minute gems of the present invention as the display elements, and particularly in perfecting the combination to include a suitable liquid in the glass housing, I 11 found that as a practical matter it was necessary to provide a condition such that at mean atmospheric temperatures there would be a sufficient portion of the'opal-free interior space of the housing 14 which would be free also of liquids, in order that at higher temperatures the liquid would be free to expand without fracturing the glass housing, notwithstanding the substantial thickness of 125 the housing wall 14 for resistance to impacts.

I found also that such air-space was much larger in volume than the minimum necessary air-space involved in sealing-off the glass housing. But the air in such a subvision'of such an air-bubble largely destroys the fascinating color effects of the preferably mobile members of the group of opal fracture. fragments 199; in fact, the great increase of the fascinating effect of the above improvements is largely discounted and negatived by the presence of such air-bubble as B. This composite opal has the effect of fascination'on the wearer herself as well as other observers. At different times of different atmospheric temperature and the changing effect thereon on the degree of viscosity of the glycerine, the movement of the opal fragments differs in Velocity and extent,t-he gem is moody; and the wearer observes the gem as an astrologer his crystal. Since in observing it, she usually holds it below eye level, and as the bubble B (lighter than liquid 15) always is at the highest part of the housing in any given angular position of the gem, the bubble, unless handled in accordance with this invention, tends to move toward, and come to rest at, a position between the eye and the group of small moving opals, the bubble threading its way along the inner surface of the housing 1i and between the opal fragments along the wall until it reaches such position of rest, and always, therefore, producing an effect, which most seriously distracts the attention of the observer from the changing colors of the opal fragments, and impairs the fascination of observing them. Bubble B would appear chiefly as a dark-line circle, as if it were a defeet in the glass-housing; but because the bubble is movable, as are the small opals, its

effect is much worse than a fixed defect in the glass. It contrasts most indistinctly not only with the small opals 199 but with the glass of the housing 14 and it tends to give an impression of vision of the housing as a separate entity and tends to impart a sense of the existence of the liquid, all as opposed to the desired impression or illusion otherwise of a unitary opal of the external dimensions of-the housing 14. The principal vice of the bubble is not in its own appearance,

but in the contrasting effect and impressions which it causes.

This freev air-space B for liquid expansion is not merely the small air volume incidental to sealin othe lass housing, for the latter may be e ected without leavin much, if any, air with the glycerine 15 insi e the housing; and even if a minute volume of air be left inside as an incident of sealing off, it may adhere in or to the minute interior cavity of the housing at the point of sealing-off so as not to affect injuriously the appearance of the ,stood that it is vision of the air-s ace B itgem. I found that the means shown in my prior patent for retaining the air-bubble of sealing off was inadequate to take care of the size of air-bubble B which is now involved in the practical commercial production of my composite opal gems. One of the advantages of my composite real opal is that it is st-urdier than the prior unitary opal, the wall of the container 14 being of comparatively thick strong glass as shown in the double scale section of Figs. 1 and 2. But I have found that even such strong, transparent housing 14 is liable to breakage by temperature-expansion of the glycerine 15 unless the volume of the glycerine is so much less than that of the total space inside the container 14 not occupied by the small opals 199, as to leave inside also a substantial volume of air B, at mean atmospheric temperature.

In the embodiments of the invention disclosed in the parent case, the air-bubble B is localized permanently at a part of the hous ing which may be sufliciently concealed by the jewel-setting as in the jewels, as pendants, v 90 finger rings and the like. But it is sufficient if other practicable means is employed to prevent the bad effects of a direct vision of the air-bubble B itself when observing the moving small gem-units. For example, in Fig. 1 is shown a modified form of means by which the liquid-expansion air-bubble itself, B, is kept from visibility although permitted to move about'among the moving gemunits 199 in housing 14. It is to be underself among the small diffused 0 al agments, which destroys the desired e ect of beauty.. In this Fig. 1, a bubble-housing 144A (shown in section) is enclosed within opal-housing 14, but 144A has a constricted opening N so that the air 13 contained in it is kept inside and prevented from escaping as a free bubble into the liquid 15 surrounding the small opals or display elements 199 and thus detracting from the effect of beaut In this 1- case housing 144A may consist 0 one of'the smal opals 199 themselves, hollowed out to contain the air B and formed with the narrow inlet opening N. Or, housing 144A may consist of an elastic substance such as rubber, in 1 which case there need be no 0 ening in it, the air B inside being encapsu ated, for as the liquid varies in volume with change in temperature, the air inside such elastic housing 144A and said housing itself will be 1 caused to vary in volume. In such case, in

order to avoid the appearance of flaw similar to an air-space, the outer surface of elastic housing 144A (not being an opal fragment) may be coated or ainted in imitation of an 1 opal or display e ement. It is not so important to cause bubble-housing 144A of Fig. 1 to exactly resemble opal fragment displayelements 199, as it is to prevent direct vision of the air-bubble B itself as constructed with 1 the esthetic features of structure; and almost any appearance of a bubble-housing 144A of Fig. 1 is preferable to the direct vision of the substantially large air-bubble B. In any form of bubble-housing 144A of Fig. 1, it is placed inside external housing 14 at the same time with the display elements 199; and, as then placed housing 144A of course contalns the llquidree space of air B necessary to at the highest tem erature to which the composite em is to e exposed in use, or that bubbleousing 144A should contain some of the liquid at the time it is introduced with display-elements 199 into gem-housing 14.

This form of Fig. 1, while not localizing bubble B fixedly away from the ordinary range of vision of the small opals (as in the parent case), yet causes the bubble or gaseous-space to be covered from view as a thing separate from or contrasting with the opal-fragments display elements 199 or with the housing. In such a form as this, there 18 no need of fixedly localizing the substantially large air' bubble out of the ordinary range of vision of the small opals 199; although the construction with constricted passage N (Fig.1) does localize the bubble permanently out of the range of vision, i. e., within the bubb1e-housing'14 which acts to cover the bubble from vision as a se arate thing. Fig. 1 therefore resembles the lbrms of the parent case in having both the localizing means and the covering means. In Fig. 1,the setting .129! e d ;tos'eal-ofi Y as a support for Y which [conceals Y;or such a 'seal-ofi conetftingsia's in Figs. 3'and 9 of the asegmay' beemployed, as shown in Fig. 2.

ig. 2 shows a modification of means 1nside housing 14 for preventing direct vision of a movable liquid-expansion air-bubble, and here as in Fi 1 irrespective of the setting (as distingulshed from Figs. 1-8 and 9-10.01 the parent case).- Here Is a housin retaining housing; but the air-bubble B is Fig. 1 of the parent case may be cement- 1 appearing bubble lacking the invention hereof, but like all the forms disclosed in the parent case in that the li .uid-expansion airubble B is substanti-a y.,.conc'ealed from 'vision as a separate contrasting. thing from the opal-fragment .displayflelements 199. In Fig. 2, -as in Fig. 1, no means'is needed to fixedly localize the bubble, 'altl 1ou 2 the bubble is localized in a coveringcon cealin it from vision as a contrasting thing. The light aluminum flakes or their equivae gh in Fig.

lents in repellingthe liquid have noother place to go than the air bubble as they try to get away from the liquid; and when they have surrounded the air bubble they cannot leave it because of their continued repulsion from the liquid. In Fig. 2 other suitablejewelsettings than that of the finger ring shown may be employed as shown in Fig. 1 of the parent case; but in any case the settmg, as has een shown preferab y more or less conceals sealofi Y. Member 144D of Fig.2, lacking passage N of Fig. 1, may be considered as illustrating also the compressible (rubber) member 144A above described in connection with Fig. 1.

The principal advantages of my composite real gem or opal are that it .is a cheaper, stronger (less-fragile) and more beautiful gem than areal gem in the form of a sin 1e unit of similar size andshape and simi ar though less beautiful appearance.

Various terms in the claims, as glass, transparent, opal? and glycerine are used as limitations but are intended to include substantial, equivalents in all cases of correspondingpatentable novelty and utility; for example,'some claims including the word opal may be, patentable, by virtue of such precise limitation, but the 'patentabilit of'some claims using the word may be su etc.,

ficient to warrant its construction to include g inventlon may be employed without a liquid 14 without any 1ntegral adjacent bubbleor in combination with features other than those disclosed herein; g

' In the drawings, there appears tobe' a minimum opal-free space in housing 14, allowing minimum freedom of movement of the small opals 199. This appearance (which is a true showing so far as concerns appearance) may be on account of viewing the composite opal directly from above, in which case the small opals, even stationary in a mass at the bottom of housing 14, will be seen as extending entirely from one side-wall of the housing to the other; whereas the fact as to the number of, small opals in the housing may be and preferably is that the opal-free liquidfilled space 15 may be many times the volume occupied by substantially large bubble B, or

the drawings may be taken as elevation views showing an actual extra-small opal-free interior housing-space allowing only limited motion of the small gems.

I particularly point out and distinct-1y claim the part. improvement, or combination which I claim as my invention or discovery, as follows:

1. A composite gem including a closed transparent housing of glass; means associated with said housing .to define a jewel chamber and a movable air chamber in the housing; a plurality of opal fracture fragments in said jewel chamber; and a transparent colorless liquid of substantial viscosity disposed in said jewel chamber.

2. A composite gem of the type described including in combination a closed transparent housing; a plurality of gem fragments in said housing; a transparent colorless liquid partially filling the housing and immersing the gem fragments but leaving a space in the housing; and means inside the transparent housing preventing a View therethru from vision of said space as a space in marked contrast with the gem fragments.

3. A composite opal including a closed substantially colorless and transparent housing, a substantial number of small opal fracture fragments inside said housing but not filling it; a substantially colorless and transparent liquid also inside the housing, in which liquid said fragments are immersed and visible as to their opalescent reflecting surfaces thru the housing and liquid; said liquid having sufficient volume for movements thru it of the opal fragments immersed in it, said liquid having sufiicient density to cause such fragment-movements to be slow enough to substantially diminish their appearance in motion as elements independent of one another, said liquid having a refractive index sufficiently close to that of the material of the housing to mask the adjacent surfaces of housing and liquid and mask their appearance as separate things; and said liquid being of insuflicient volume to fill the housing but leaving a space therein of sufficient size to prevent undue stresses on the housing upon tenlpcrature-cxpansion of the liquid; and means movable thru said liquid with the opal fragments and surrounding said space sufficiently to prevent vision of the space in marked contrast with the opal fragments.

4. A composite opal including a closed substantially colorless and transparent hollow housing, a substantially large number of opal fracture fragments respectively having a plurality of opalescent fracture faces and also located in said housing; a substantially colorless and transparent liquid also located inside the housing and i-iurrounding said fragments, the opal fragments and liquid leaving a relatively small space in the housing preventing undue stresses thereon by temperature-expansion of the liquid; and a second hollow housing located within and enclosed by the first and immersed in the liquid therein and enclosing said space and formed with a constricted opening communicating between said space and liquid.

HORACE H. WELCH.

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