Rhyolite Gemstone & Information | Gemopedia by JTV | Gemopedia™
Rhyolite is a volcanic rock similar in its chemistry to granite. Most rhyolites are porphyritic, with larger crystals in a fine-grained matrix of crystals too small to been seen with the naked eye. Rhyolite is silica-rich, giving it a light range of color, often found with banding throughout. This beautiful stone is often used in ornamentation.
Beige, Brown, Red, Orange, Green, White To Gray
Rhyolite classificationCommonNameRhyoliteSpeciesRhyoliteVarietyColorsBeige, Brown, Red, Orange, Green, White To GrayAlternateNamesHickoryite, Rainbow Hickoryite, Spiderweb Rhyolite, Birds Eye Rhyolite, Mushroom Rhyolite, WonderstoneGemstoneGroupsKeySeparationsClassificationCommentsRhyolite is a extrusive igneous rock composed of mostly quartz and feldspar and is often mistaken for jasper. Hickoryite is a banded version of rhyolite. Rainbow hickoryite is a muti-color banded form of rhyolite. Misnomers: butterfly jasper, rain forest jasper, solar flare jasper, Nevada paint jasper, lily pad jasper, leopard jasper, mushroom jasper and Mexican poppy jasper
Rhyolite chemistry & crystallographyChemicalNamesilicon dioxide + potassium OxideChemicalFormulaSiO2+K2OSynthesisCrystalSystemNAChemistryClassificationRockNatureNaturalCrystallinityAggregateChemistryComments
Rhyolite optical propertiesTransparencyOpaqueDispersionOpticalCommentsRefractiveIndexBirefringenceOpticCharacterNAOpticSignNAPolariscopeReactionFluorescenceSWUV:
Rhyolite characteristic physical propertiesHardness6.5-7CharacteristicCommentsStreakSpecificGravityToughnessInclusionsRhyolite might show banding or spherical growth. If stones are viewed in cross-section using magnification they typically show crystalline growth and may show radiating needle patterns.LusterStabilityFractureCleavageNone