Kaatialaite [Fe(H2AsO4)3·5H2O] is a ferric arsenate mineral found in Finland. It is a ferric arsenate mineral. It was named after the type locality in the Kaatiala pegmatite in Finland. It is a rare mineral that occurs in granite pegmatites and in oxidized silver-arsenic veins in gabbro. Additional localities including in Germany, the Czech Republic, and the United States.
- Category: Arsenate mineral
- Formula: [Fe(H2AsO4)35H2O]
- Crystal system: Monoclinic (Unknown space group)
- Kaatialaite is Not Radioactive
The water content of the mineral is variable depending on relative humidity. It will also become cloudy upon exposure to light. Associated minerals include arsenolite, lollingite, calcite, and gypsum.
- Color: Greenish blue, gray, yellow, white
- Streak: White
- Diaphaneity: Transparent
- Specific Gravity: 2.64
- Luster: Earthy
- Transparency: Translucent
Occurrence: A secondary mineral in a granite pegmatite (Kaatiala pegmatite, Finland); in an oxidized Ag–As vein in gabbro (Niederbeerbach, Germany).
Association: Arsenolite, l¨ollingite, calcite, gypsum (Kaatiala pegmatite, Finland).