Untitled Flashcards Set

Abalone

Also known as ear-shells, they produce pearls of various hues including greens, yellows, and blues.

Abrasive Material

Hard and sometimes brittle substances used for abrading and polishing purposes; examples include diamond dust, boron carbide, and aluminum oxide.

Absorption Spectra

The pattern of dark lines or bands seen when light has passed through a gemstone and is examined by a spectroscope.

Achroite

Colourless tourmaline.

Acid Rocks

A subdivision of the igneous group of rocks, generally light in color with a high silica content.

Amethyst

A purple variety of quartz that is considered a birthstone for February.

Allochromatic Minerals

Minerals that are colourless when pure but may be coloured by impurities.

Amber

Fossilized tree resin available in a variety of colors, commonly yellow to orange.

Aquamarine

A light blue member of the beryl family, often tinted with green.

Beryl

A mineral family that includes several gemstones, such as emerald and aquamarine.

Chatoyancy

The optical phenomenon seen in stones, such as cat's-eye, where a band of light appears across the surface.

Diamond Dust

The most important abrasive material made of diamonds used in various grain sizes.

Emerald

A class of gemstones that is a green variety of beryl.

Fluorescence

The effect exhibited by certain materials of producing visible light when irradiated.

Iridescence

The prismatic colors seen in cracks and flaws in a stone, often observed in opals.

Pleochroism

The optical effect of certain gemstones showing different colors when viewed from different angles.

Rutile

A mineral composed primarily of titanium dioxide, known for its needle-like inclusions.

Tourmaline

A complex borosilicate mineral known in many colors, including green, blue, and pink.

Zircon

A mineral known for its wide range of colors and high dispersion, forming high-RI gemstones.

Diffusion

The process of substituting colors in stones, typically through heat treatments.

Synthetic Stones

Man-made creations that simulate genuine gemstones.

Star Facets

The triangular facets that surround the table in a brilliant-cut stone.