Achtaragdite, grey brown single tetrahedral crystals; Achtarandite is
long considered to be a mixture of grossular, kaolin, clinochlore and dolomite
pseudo probably after helvite; Recent investigations by Galuskin & Galuskina
(2002) showed the crystals to be sponge-like hibschite pseudomorphs after
a wadalite-like mineral. Very interesting and confusing stuff !!
Origin: Akhtaragda River, near the settlement of Chernchevsky, southern
Yakutia, Siberia, Russia
Sample size: 3 x 3 cm (top), 2 x 2 cm (bottom)
Origin: Bellerberg, Eifel, Germany
Sample size: micromount
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