Deep Indigo Victoria Stone Cabochon 22.8 mm x 15.8 mm (quarter circle)
- Material: Victoria Stone
- Mohs Hardness: 5.5 - 6.0
- Dimensions: 22.8 mm x 15.8 mm x 5.61 mm (mm = millimeters)
- Weight: 7.81 carats Victoria Stone (approx.)/ 13.25 carats total
- Type: synthesized/reconstructed from natural materials
- Backing depth: 2.3 mm
- Backing material: Jet
- Treatment: None
This cabochon is cut from material that was manufactured by Iimori Laboratory, Ltd. of Tokyo Japan. This is a highly chatoyant Deep Indigo (indigo blue) Victoria Stone that has been backed with Jet. Victoria Stone has a chatoyancy similiar to Pietersite or Hawk's Eye, but with patterns and colors that are totally unique. Genuine Victoria Stone cabochons of this quality are becoming rare.
Produced between 1969 and 1990, Victoria Stone (also popularly known as Iimori-stone) is a radially developed crystalline mass of fibrous aggregate-structure. It was made by crushing a variety of natural minerals (quartz, feldspar, magnesite, calcite, fluorspar, etc.) into a fine powder. This powder was then heated to a molten state causing the different minerals to fuse together and form a new mineral of fine fibrous aggregate structure. Similar to nephrite jade of the amphibole mineralogical group, Victoria Stone differs from nephrite in the quantity, and crystal structure, of the actinolite they both contain.
The brilliant chatoyance exhibited by Victoria Stone is the result of excess actinolite particles. Actinolite was added to a special crystallizing agent that, along with crystal habit regulators, would be mixed with the molten magma base minerals in quantities sufficient to influence the crystallization of the new mineral. The excess actinolite particles crystallize in fan shaped patterns during the mineralization process. The interplay of light and these crystal fan structures is responsible for producing the optical effect we call chatoyancy. The amount of crystallizing agent that was added to the base minerals had a direct impact on the level of chatoyancy seen in the finished product. This resulted in the ability to produce a number of different stones simply by varying the amount of crystallizing agent that was added to the base magma during production. A good example of this is Meta-jade.
At the same time they were producing Victoria Stone, Iimori Laboratory, Ltd. produced an artificial jade called Meta-jade. Long considered to be the highest grade imitation of genuine Jadeite jade available, it was made using same process and base minerals as Victoria Stone. However, only a limited amount of the crystallizing agent with actinolite was added to the molten Meta-jade base minerals during production. As a result the chatoyance found in Victoria Stone is completely absent from Meta-jade.
The Victoria Stone in this cabochon is backed with 2.30 millimeters of Jet to strengthen and protect the stone, this also lifts the gem material so it isn't conceled by the bezel when mounted. With this cabochon, over 3.31 millimeters of highly polished Victoria Stone can be exposed above the bezel.
Visit www.gemtreecreativedesigns.com for more information about Victoria Stone and the other synthesized gemstones produced by Iimori Laboratory, Ltd.
- Finished Deep Indigo 22.8 mm x 15.8 mm Victoria Stone Cabochon (arrow)
- Informational pamphlet on IL - Stone