Composite gemstone and method of production thereof

Abstract

The invention discloses a composite gemstone for use in jewelry, formed of two or more adjacent precious stones, bonded to one another in a permanent manner without use of adhesive. The appearance is that of a single homogenous stone, with high grade optical properties as measured spectroscopically. “Low height” diamonds may be used for forming the composite, when to date such low height diamonds are considered non-profitable for jewelry. A process for the production of such composite gemstones is disclosed.

1 . A composite gemstone comprised of an upper precious stone and a lower precious stone, bonded to one another permanently without use of adhesive, wherein said contact points of said upper stone and said lower stone are highly polished; wherein the visual appearance is of a single gemstone. 
     
     
         2 . The composite gemstone of  claim 1 , wherein said upper and said lower precious stones are bonded by means of vacuum. 
     
     
         3 . The composite gemstone of  claim 2 , wherein said vacuum is an absolute vacuum formed using a casimir effect. 
     
     
         4 . The composite gemstone of  claim 1 , wherein said upper precious stone and said lower precious stone may be selected independently from a material of the following group:
 diamond, sapphire, spinel, topaz, quartz and spinel.   
     
     
         5 . The composite gemstone of  claim 1 , wherein one or both of said lower precious stone and said upper precious stone are low height diamonds, wherein the height of said rough stone is within the approximate range of 1.5-3.8 mm prior to cutting. 
     
     
         6 . The composite gemstone of  claim 1 , wherein the height of at least one of said lower and upper precious stones is 4.8 mm. 
     
     
         7 . The composite gemstone of  claim 1 , wherein at least one of said precious stones is a fancy colored diamond. 
     
     
         8 . The composite gemstone of  claim 1 , wherein a ratio of 63% of height to diameter is maintained in said composite for optimal light refraction. 
     
     
         9 . The composite gemstone of  claim 1 , said composite comprising matched facets between said upper and said lower precious stones. 
     
     
         10 . A composite gemstone having two or more precious stones bonded to one another permanently without use of adhesive, produced using the following process:
 a) providing two or more precious stones as a matched set, for use in a single composite stone, wherein said stones are polished and cut to desired geometrical sizes and shapes;   b) clamping each of said precious stones so as to expose surfaces which will be bonded to adjacent precious stones in said composite; and rotating said precious stones at approximately 2000-4000 RPM, while polishing said exposed surfaces of said precious stones;   c) cleaning said precious stones;   d) clamping said precious stones and rotating said precious stones at a speed of approximately 500-1500 RPM in opposite rotational orientation; contacting said precious stones with one another at a desired orientation until vacuum is sensed; halting said rotation;   thus obtaining a composite gemstone having two or more precious stones bonded together in a permanent manner without use of adhesive.   
     
     
         11 . The composite gemstone of  claim 10 , wherein in step b) said precious stones are polished until a nano-surface smoothness is obtained. 
     
     
         12 . The composite gemstone of  claim 10 , wherein said precious stones are maintained in sterile conditions after step c) is performed until step d) is begun. 
     
     
         13 . The composite gemstone of  claim 10 , wherein step c) of cleaning comprises boiling said stones overnight in a mixture of hydrochloric acid, sulfuric acid and cyanide, followed by rinsing in distilled water. 
     
     
         14 . The composite gemstone of  claim 10 , wherein in step d) said precious stones contact one another at a pressure of 10 PSI. 
     
     
         15 . A process for preparing a composite gemstone having two or more precious stones bonded to one another permanently without use of adhesive, said process comprising:
 a. providing two or more precious stones as a matched set, for use in a single composite stone, wherein said stones are polished and cut to desired geometrical sizes and shapes;   b. clamping each of said precious stones so as to expose surfaces which will be bonded to adjacent precious stones in said composite; and rotating said precious stones at approximately 2000-4000 RPM, while polishing said exposed surfaces of said precious stones;   c. cleaning said precious stones;   d. clamping said precious stones and rotating said precious stones at a speed of approximately 500-1500 RPM in opposite rotational orientation; contacting said precious stones with one another at a desired orientation until vacuum is sensed; halting said rotation;   
       thus obtaining a composite gemstone having two or more precious stones bonded together in a permanent manner without use of adhesive.