Gemstones - Aciform
Gemstones - Aciform Aciform means needle-shaped and is closely related to the term acicular. It describes minerals or crystal formations that resemble slender needles. The term originates from Latin words referring to needle-like forms. Such structures a
Gemstones - Acentela
Gemstones - Acentela Acentela is a Spanish term used for rock crystal. Rock crystal is the transparent and colorless variety of quartz. It has been admired for centuries because of its clarity and brilliance. The material is found in many regions around
Gemstones - Abalone
Gemstones - Abalone Abalone is the common name for the marine mollusc known scientifically as Haliotis. It is also called an ormer or ear-shell because of its distinctive shape. Abalone species are found in the Pacific waters of California, Mexico, Japan
Gemstones - Abalone Pearl
Gemstones - Abalone Pearl An abalone pearl is a pearl produced by an abalone mollusc. Most examples are blister pearls attached to the inner shell. True free pearls occur less frequently and are highly prized. Important sources include the coastal waters
Gemstones - Aberration
Gemstones - Aberration Aberration is the failure of a lens or mirror to bring light rays to a common focus. It is an important concept in optics and gemology. Aberration can reduce the clarity of images viewed through optical instruments. This may affect
Gemstones - Abrade
Gemstones - Abrade Abrade means to wear away a material through friction or rubbing. The term is commonly used in gemology and lapidary work. Abrasion occurs when one surface rubs against another surface repeatedly. This action gradually removes small am
Gemstones - Abrasive
Gemstones - Abrasive An abrasive is a substance used to wear away another material through friction. Abrasives are essential tools in gemstone cutting and polishing. They are usually harder than the materials they act upon. Their purpose is to remove, sh
Gemstones - Absorption
Gemstones - Absorption Absorption is the process by which a gemstone takes in certain portions of light. White light contains all the colors of the visible spectrum. As light passes through a gemstone, some wavelengths are absorbed. The remaining wavelen
Gemstones - Absorption Bands
Gemstones - Absorption Bands Absorption bands are dark regions that appear within a gemstone’s spectrum. They represent wavelengths of light that have been absorbed by the material. These bands are visible when a gemstone is examined with a spectroscope.
Gemstones - Absorption Lines
Gemstones - Absorption Lines Absorption lines are narrow dark lines that appear within a spectrum. They indicate specific wavelengths of light that have been absorbed by a gemstone. In many cases, the terms absorption lines and absorption bands are used