
mineral
Turquoise and Red Coral
Turquoise: CuAl6(PO4)4(OH)8·4H2O; Red Coral: Corallium rubrum (organic gemstone)
AI-generated identification · may be incorrectTurquoise: Hardness 5-6, sky blue to green, waxy to subvitreous luster, triclinic. Red Coral: Hardness 3-4, vivid red/orange, calcium carbonate composition, dull luster when raw to high polish.
Identified More mineral →
Explore Turquoise and Red Coral in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Turquoise: Hardness 5-6, sky blue to green, waxy to subvitreous luster, triclinic. Red Coral: Hardness 3-4, vivid red/orange, calcium carbonate composition, dull luster when raw to high polish.
Formation & geological history
Turquoise forms via hydrothermal processes in aluminum-rich rock near copper deposits. Red Coral is an organic gemstone formed by marine polyps in deep, dark seawater environments, typically in the Mediterranean Sea.
Uses & applications
Predominantly used in jewelry (rings, necklaces, bracelets) and ornamental carvings. They are staple materials in Native American (especially Navajo and Zuni) jewelry styles.
Geological facts
Turquoise is one of the oldest known gemstones, used by Ancient Egyptians and Persians. Red Coral is considered a 'biological gemstone' rather than a mineral, as it is produced by living organisms.
Field identification & locations
Identify Turquoise by its opaque blue-green color and potential brown/black matrix; check for 'reconstitution' or dyed magnesite clones. Identify Coral by its unique growth patterns and lack of reaction to heat (plastic melts). Historically significant in Southwestern US and Tibetan cultures.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous