mineral

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Hardness: 1-2 (Mohs scale), Color: Grayish-white to tan, Luster: Dull/Earthy, Crystal Structure: Monoclinic, Cleavage: Perfect basal

Identified February 21, 2026More mineral →

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Physical properties

Hardness: 1-2 (Mohs scale), Color: Grayish-white to tan, Luster: Dull/Earthy, Crystal Structure: Monoclinic, Cleavage: Perfect basal

Formation & geological history

Formed via the chemical weathering of primary silicate minerals like feldspar and mica in tropical, high-moisture environments. Common in Cenozoic era topsoils.

Uses & applications

Used in ceramics, as a soil conditioner for agriculture, and as a raw material for brick-making.

Geological facts

The yellowing and browning on the banana leaf pictured often indicates a deficiency in soil minerals like potassium or magnesium, or presence of fungal pathogens in the soil.

Field identification & locations

Identified by soapy feel when wet and earthy odor. Found globally in wet tropical regions. Collectors look for high purity and low organic content.

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Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral