Stewartite - Sold
- Stewart mine
- Pala district
- San Diego County
- 6.5 by 4.3 by 3.4 – Small cabinet specimen (under 10 cm)
Stewartite is a manganese iron phosphate. Schaller (1912) named the mineral after this locality. Moore & Araki (1974) solved the crystal structure and demonstrated polymorphic relationships with laueite and pseudolaueite. Stewartite has a bright yellow color, here forming microcrystals with contrasting purple phosphosiderite. The matrix for this specimen is altered lithiophillite which has been partly leached of its lithium content, turning into a soft charcoal like mass. This specimen was part of the personal collection of Ralph Merrill, proprietor of the prolific mail order business Minerals Unlimited, obtained in 1955. Specimens of type locality stewartite are rarely available, and missing in many San Diego County collections.