Talc pseudomorph after Forsterite (ex Kay Robertson Collection)

Item Description

A strange and obviously rare example of Talc forming a pseudomorph after preexisting Forsterite crystals from the Mackinaw Mine in Snohomish County, Washington. The piece is the only one of its kind that we've seen, and considering that neither species is reported from the mine on mindat, this is certainly an incredibly rare specimen from this copper, nickel, cobalt, gold, silver mine in upper northwest Washington state. Ex Kay Robertson Collection (#10216). Kay is a prominent California collector, who specialized in European classics (see the article in the March-April, 2007 Mineralogical Record).