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.

Contents 1 Types of Gemstones 1.1 Apatite 1.2 Azurite 1.3 Benitoite 1.4 Beryl 1.4.1 Aquamarine 1.4.2 Emerald 1.4.3 Heliodore 1.4.4 Morganite 1.5 Chalcedony 1.5.1 Agate 1.5.2 Aventurine 1.5.3 Black Chalcedony / Black Onyx 1.5.4 Bloodstone 1.5.5 Carnelian 1.5.6 Chrysoprase 1.5.7 Heliotrope 1.5.8 Jasper 1.6 Chrysocolla 1.7 Chrysoberyl 1.7.1 Alexandrite 1.7.2 Cat's Eye 1.8 Cordierite 1.8.1 Iolite 1.9 Corundum 1.9.1 Ruby 1.9.2 Sapphire 1.10 Diamond 1.11 Diopside 1.11.1 Chrome Diopside 1.12 Feldspar 1.12.1 Moonstone 1.12.2 Sunstone 1.13 Fluorite 1.14 Garnets 1.14.1 Almandite 1.14.2 Andratite 1.14.3 Grossularite 1.14.4 Malaya 1.14.5 Pyrope 1.14.6 Spessartine 1.14.7 Uvarovite 1.15 Grossularite 1.16 Hematite 1.17 Jadeite 1.17.1 Jade 1.18 Kyanite 1.19 Labradorite 1.20 Lapis Lazuli 1.21 Malachite 1.22 Nephrite 1.22.1 Jade 1.23 Olivine 1.23.1 Peridot 1.24 Opal 1.25 Organic 1.25.1 Amber 1.25.2 Corel 1.25.3 Ivory 1.25.4 Jet 1.25.5 Pearl 1.25.6 Shell 1.25.7 Tortoise Shell 1.26 Quartz 1.26.1 Amethyst 1.26.2 Ametrine 1.26.3 Citrine 1.26.4 Rock Crystal 1.26.5 Rose Quartz 1.26.6 Smoky Quartz 1.26.7 Tiger's Eye Quartz 1.27 Rhodochrosite 1.28 Sinhalite 1.29 Sodalite 1.30 Sphene 1.30.1 Titanite 1.31 Spinel 1.32 Sugilite 1.33 Spodumene 1.33.1 Hiddenite 1.33.2 Kunzite 1.34 Topaz 1.35 Tourmaline 1.36 Turquoise 1.37 Zircon 1.38 Zoisite 1.38.1 Tanzanite 2 History 3 Gem Identification 3.1 Issues 4 Imitations 5 Treatments

Types of Gemstones

Apatite

Azurite

Benitoite

Beryl

Aquamarine

Emerald

Heliodore

Morganite

Chalcedony

Agate

• Dendritic Agate / Scenic Agate
• Eye Agate / Orbicular Agate
• Fire Agate
• Iris Agate
• Landscape Agate
• Sardonyx / Sard

Aventurine

Black Chalcedony / Black Onyx

Bloodstone

Carnelian

Chrysoprase

Heliotrope

Jasper

Chrysocolla

Chrysoberyl

Alexandrite

Alexandrite

Cat's Eye

Cordierite

Iolite

Corundum

Ruby

• Star Ruby

Sapphire

• Star Sapphire

Diamond

Diopside

Chrome Diopside

Feldspar

Moonstone

Sunstone

Fluorite

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'.

Almandite

• Demantoid
• Rhodolite

Andratite

Grossularite

• Hessonite
• Tsavorite

Malaya

Pyrope

• Rhodolite

Spessartine

Uvarovite

Grossularite

Hematite

Jadeite

Jade

Kyanite

Labradorite

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'.

Malachite

Nephrite

Jade

Olivine

Peridot

Opal

Organic

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.

Corel

Ivory

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.

Pearl

Shell

Tortoise Shell

Quartz

Amethyst

Ametrine

Citrine

Rock Crystal

Rose Quartz

Smoky Quartz

Tiger's Eye Quartz

Rhodochrosite

Sinhalite

Sodalite

Sphene

Titanite

Spinel

Sugilite

Spodumene

Hiddenite

Kunzite

Topaz

• Blue Topaz
• Red Topaz

Tourmaline

• Green Tourmaline
• Paraiba Tourmaline
• Tri-color Tourmaline

Turquoise

Zircon

Zoisite

Tanzanite

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 apparent value of stones.