Rhyolite Gemstone & Information | Gemopedia by JTV | Gemopedia™

Rhyolite

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.

Colors

Beige, Brown, Red, Orange, Green, White To Gray

  • Rhyolite classification

    CommonName
    Rhyolite
    Species
    Rhyolite
    Variety
    Colors
    Beige, Brown, Red, Orange, Green, White To Gray
    AlternateNames
    Hickoryite, Rainbow Hickoryite, Spiderweb Rhyolite, Birds Eye Rhyolite, Mushroom Rhyolite, Wonderstone
    GemstoneGroups
    KeySeparations
    ClassificationComments
    Rhyolite 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 & crystallography

    ChemicalName
    silicon dioxide + potassium Oxide
    ChemicalFormula
    SiO2+K2O
    Synthesis
    CrystalSystem
    NA
    ChemistryClassification
    Rock
    Nature
    Natural
    Crystallinity
    Aggregate
    ChemistryComments
  • Rhyolite optical properties

    Transparency
    Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    Birefringence
    OpticCharacter
    NA
    OpticSign
    NA
    PolariscopeReaction
    Fluorescence
    SWUV:
    LWUV:
    CCFReaction
    Pleochroism
    None
  • Rhyolite characteristic physical properties

    Hardness
    6.5-7
    CharacteristicComments
    Streak
    SpecificGravity
    Toughness
    Inclusions
    Rhyolite 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.
    Luster
    Stability
    Fracture
    Cleavage
    None