Difference between revisions of "Enhancement of gems"

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Processes which alter the appearance of a [[gemstone]] are known in the jewlers' trade as '''enhancements'''. While some treatments, such as ''irradiation'', are strictly [[modern]] many enhancements of gemstones date back to [[ancient]] times.
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Processes which alter the appearance of a [[gemstone]] are known in the jewlers' trade as '''enhancements'''. While some treatments, such as ''irradiation'', are strictly [[modern]] many enhancements of gemstones date back to [[ancient]] times. Enhancement is a controversial subject. [[Pliny]] condemned the practice and considered it to be a type of fraud. Even among modern jewlers the practice was a taboo subject for discussion, at least where customers were concerned. Modern trade laws, however, require jewlers to reveal all known enhancements.
  
 
Traditional enhancments:
 
Traditional enhancments:
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*reconstitution
 
*reconstitution
 
*irradiation
 
*irradiation
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== Cutting: ==
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Modern jewelers do not consider the cutting of gems to be an enhancement since it does not alter the color or texture of the stones. Nevertheless, cutting and polishing are among the oldest means of improving a gemstone's appearance. Traditional cuts include the following:
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*baroques (gemstones left in their natural pebble shape are known as ''baroques''. Orginally these were found in river beds--later the technique was developed for polishing baroques in tumbling barrels. Baroque stones preserve the original weight of the gem; also, there was a widespread belief that cutting a gemstone would hurt or mar its mystical powers)
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*drilled beads (beaded necklaces were very popular in ancient times, and also among the Norse. The stones would be fashionef as balls or other simple shapes, and then drilled with bow drills. Pliny also mentions that the [[India]]ns would leave [[emerald]]s and other [[beryl]]s in their natural crystalline shape--a hexagonal prism--and drill out the pith)
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*cabochons
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*rough facets

Revision as of 02:18, 14 May 2006

Processes which alter the appearance of a gemstone are known in the jewlers' trade as enhancements. While some treatments, such as irradiation, are strictly modern many enhancements of gemstones date back to ancient times. Enhancement is a controversial subject. Pliny condemned the practice and considered it to be a type of fraud. Even among modern jewlers the practice was a taboo subject for discussion, at least where customers were concerned. Modern trade laws, however, require jewlers to reveal all known enhancements.

Traditional enhancments:

  • cutting & polishing (not strictly an enhancement in the traditional sense, but will be considered here none-the-less)
  • dyeing (see also the entry on agate)
  • heat treating
  • oiling
  • waxing

Modern enhancements:

  • improved heat treating
  • reconstitution
  • irradiation

Cutting:

Modern jewelers do not consider the cutting of gems to be an enhancement since it does not alter the color or texture of the stones. Nevertheless, cutting and polishing are among the oldest means of improving a gemstone's appearance. Traditional cuts include the following:

  • baroques (gemstones left in their natural pebble shape are known as baroques. Orginally these were found in river beds--later the technique was developed for polishing baroques in tumbling barrels. Baroque stones preserve the original weight of the gem; also, there was a widespread belief that cutting a gemstone would hurt or mar its mystical powers)
  • drilled beads (beaded necklaces were very popular in ancient times, and also among the Norse. The stones would be fashionef as balls or other simple shapes, and then drilled with bow drills. Pliny also mentions that the Indians would leave emeralds and other beryls in their natural crystalline shape--a hexagonal prism--and drill out the pith)
  • cabochons
  • rough facets