Diadochite

Diadochite, also known as destinezite, is a clay mineral. It is a secondary mineral formed by the weathering and hydration of other minerals. Its formula is Fe2(PO4)(SO4)OH·5H2O.It has a greenish yellow to brown colour and forms nodules or crusts. Its appearance has been compared to cauliflower.Identified originally in Belgium in 1831, it has been found in many places throughout the world.
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General Information:
 Chemical Formula:
Fe+++2(PO4)(SO4)(OH)·6(H2O)
 Composition:
(Molecular Weight = 427.83 gm)
Iron 26.11 % Fe
Phosphorus 7.24 % P 
Hydrogen 3.06 % H 
Sulfur 7.50 % S 
Oxygen 56.10 % O 
 Empirical Formula:
Fe3+2(SO4)(PO4)(OH)·6(H2O)
 Locality:
Ansbach, Thuringia, Germany.
 Name Origin:
From the Greek, diadochos, meaning "successor," presumably in allusion to its secondary origin.
Physical Properties:
 Cleavage:
None
 Color:
yellow, brown, yellowish green, cinnamon brown, or yellowish white.
 Density:
2 - 2.4, Average = 2.2
 Diaphaniety:
Translucent to Opaque
 Habits:
Encrustations - Forms crust-like aggregates on matrix., Nodular - Tuberose forms having irregular protuberances over the surface., Stalactitic - Shaped like pendant columns as stalact ites or stalagmites (e.g. calcite).
 Hardness:
3-3.5 - Calcite-Copper Penny
 Luster:
Waxy
 Streak:
yellow
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