Moss Agate Gemstone & Information | Gemopedia by JTV | Gemopedia™

Moss Agate

Moss agate is a variety of chalcedony with contrasting white and green moss-like patterns. Its green coloration comes from a mineral called chlorite, while the reds and browns come from manganese oxide or the oxidation of iron hornblende. Moss agate is generally cut into thin slabs and polished to best display its natural patterns. Often moss agate cabochons are used in distinctive jewelry designs.

Colors

Colorless With Black, Brown, Red, Green Inclusions

  • Moss-agate classification

    CommonName
    Moss Agate
    Species
    Quartz
    Variety
    Chalcedony
    Colors
    Colorless With Black, Brown, Red, Green Inclusions
    AlternateNames
    Tree Agate
    GemstoneGroups
    KeySeparations
    RI, SG, appearance and fracture
    ClassificationComments
  • Moss-agate chemistry & crystallography

    ChemicalName
    silicon dioxide (aka silica)
    ChemicalFormula
    SiO2
    Synthesis
    CrystalSystem
    Trigonal
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Polycrystalline
    ChemistryComments
  • Moss-agate optical properties

    Transparency
    Transparent - Semitranslucent
    Dispersion
    Strength: none
    OpticalComments
    RefractiveIndex
    1.535-1.539
    Birefringence
    0.004-0.004
    OpticCharacter
    Uniaxial
    OpticSign
    Positive
    PolariscopeReaction
    Aggregate (AGG)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    None
  • Moss-agate characteristic physical properties

    Hardness
    6.5-7
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.55-2.7 Typical:2.6
    Toughness
    Excellent
    Inclusions
    The stone has dendritic, chlorite or hornblende mineral inclusions that have the appearance of moss.
    Luster
    Vitreous
    Stability
    Good
    Fracture
    Conchoidal, Granular
    Cleavage
    None