Tree Agate (also known as Dendritic Agate)
Quartz var. Agate (Dendritic) · Semi-Precious Gemstone; Decorative Stone
Crystal System
Trigonal (Hexagonal) crystal system; typically occurs in massive Microcrystalline or Cryptocrystalline forms
Mineral Group
Silicates (Tectosilicate subgroup; Quartz family)
Chemical Formula
SiO2 with trace inclusions of Manganese oxides or Iron silicates/Chlorite
Formation Process
Hydrothermal formation in volcanic or metamorphic host rocks where silica-rich fluids fill cavities and cracks, depositing minerals over time
About This Crystal
An opaque, white to off-white chalcedony featuring moss-like or tree-like green dappled patterns. It has a vitreous to waxy luster and a smooth, polished surface as seen in this carved mushroom form.
Physical Characteristics
Color: Mottled white and dark green; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.60–2.65; Fluorescence: Usually inert or faint yellowish-white
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: Low (0.009); Pleochroism: None; Optical Character: Uniaxial positive
Hardness & Durability
Origin Region
Mainly India (noted for high-quality deposits), Brazil, Uruguay, and parts of the United States and Kazakhstan
Hardness & Durability
Mohs Hardness: 6.5–7; highly durable and tough for jewelry and carvings due to its microcrystalline structure
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals or ultrasound. Generally stable in sunlight but should be stored separately from harder gems like Topaz or Sapphire
Rarity & Value
Common and widely available; value is determined by the aesthetic balance of the white background and green 'foliage' patterns; very affordable in carved forms.
Special Characteristics
Dendritic inclusions (though Tree Agate specifically refers to the dappled green variety, unlike the branch-like Manganese 'moss' in Moss Agate); Opaque transparency distinguishes it from translucent Moss Agate
Lore & History
Historically associated with agriculture and 'planting' intentions for abundance. In metaphysical traditions, it is known as a stone of inner peace and connection to nature, often linked to the Heart Chakra.