mineral
Dendritic Agate / Chalcedony
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Hardness: 6.5-7 on Mohs scale; Color: translucent white to grey base with dark black/brown tree-like or fern-like dendritic inclusions; Luster: vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: none, conchoidal fracture.
- Hardness
- 6
- Luster
- vitreous to waxy
Identified More mineral →
Explore Dendritic Agate / Chalcedony in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 on Mohs scale; Color: translucent white to grey base with dark black/brown tree-like or fern-like dendritic inclusions; Luster: vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: none, conchoidal fracture.
Formation & geological history
Formed when manganese and iron oxide solutions seep into micro-fractures in silica-rich fluids as chalcedony crystallizes, forming branch-like patterns.
Uses & applications
Popular for lapidary work, jewelry making (cabochons, pendants), metaphysical uses, and gemstone collections.
Geological facts
The word 'dendrite' comes from the Greek word 'dendron', meaning tree. Despite their plant-like appearance, these inclusions are purely inorganic mineral formations.
Field identification & locations
Look for translucent to opaque chalcedony containing branch-like, fern-like, or mossy black and brown inclusions. Commonly found in India, Brazil, Madagascar, and the western United States.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock