The mineral occurs extensively in Cornwall as surface deposits on Bodmin Moor, for example, where there are extensive traces of an hydraulic mining method known as streaming.
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Fighting over cassiterite deposits (particularly in Walikale) is a major cause of the conflict waged in eastern parts of the Democratic Republic of the Congo.
In particular, it focuses on the cassiterite mine in Bisie.
Further, the municipality of Castro Verde is crossed by the Iberian Pyrite Belt, composed of a massive volcanogenic sulfide deposit (VMS) associated with the polymetallic flanks of volcanic cones in the form of pyrite, chalcopyrite, sphalerite, galena and cassiterite, that begins in Aljustrel, spreads through the lower Alentejo and extends into southern Spain.
In April 2009, Senator Sam Brownback (R-KS) introduced the Congo Conflict Minerals Act of 2009 (S. 819) to require electronics companies to verify and disclose their sources of cassiterite, wolframite, and tantalum.
Pharmacosiderite, Cassiterite and Wolframite of specimen quality have also been recovered from the mine.
In mines where wolframite was mixed with cassiterite, such as South Crofty and East Pool mine in Cornwall or with bismuth such as at the Shepherd and Murphy mine in Moina, Tasmania, magnetic separation was used to separate the ores.
Material from the Siglio XX Mine, Llallagua, Bolivia, is an unusual pale yellow color, rather than the more common blue or green, forming crusts on quartz and cassiterite, and enclosing crude octahedral jeanbandyite crystals with orange colored shells of plumbogummite.