Gemstones
Gemstones
Also known as Gems, Jewels and Precious Stones. Most gemstones are classified as minerals with rare exceptions such as pearls, amber, coral and jet.
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Types of Gemstones
Amber
Although found in the earth Amber is was produced by living organisms and is not considered a mineral, instead being classified as a mineraloid.
Chalcedony
Agate
- Dendritic Agate / Scenic Agate
- Eye Agate / Orbicular Agate
- Fire Agate
- Iris Agate
- Landscape Agate
Jet
Although found in the earth Jet is was produced by living organisms and is not considered a mineral, instead being classified as a mineraloid.
Lapis Lazuli
Lapis lazuli is a mixture of minerals lazurite, calcite and sometimes pyrite and is classified as a rock. In the jewelry industry it is often referred to simply as 'lapis'.
Garnets
Unlike other gem families whose color variations result due to the presence of impurities, garnets colors are due to differences in their actual chemical structure. Therefore they are classified as a 'group' unlike other families that are classified as a 'species'.
History
Throughout history people have always admired the beauty of gemstones and due to their rarity, placed have value on them.
Gem Identification
Methods used to identify gems from similar looking species, separate them from imitations and to recognize enhancements and treatments. Since most gemstones are minerals that have a uniform chemical composition, giving them a consistent set of physical and optical properties, accurate measurement of these properties greatly helps gem identification.
Issues
Largest issues of gem identification are failing to consider all possibilities and misinterpreting test results.
Imitations
High value of gems have led to various forms of imitations over the years.
Treatments
Treatments developed to raise apperent value of stones.