Cordierite (rare Italian locality)

Item Description

Here we have a fine quality and very rarely seen specimen of Cordierite from the Roccatederighi area in Tuscany, Italy. The entry for this locality on mindat.org states that the rocks where these specimens are found is, "a cluster of rhyolitic endogenous and exogenous lava domes ", and it goes on to say that, "the peculiarity of Roccatederighi rocks is the presence of magmatic cordierite crystals". This piece is the ONLY specimen of this material that I can remember having to offer, and it features well-formed, euhedral, dark brownish colored prismatic crystals of Cordierite measuring up to 7 mm on matrix. There's a possibility that the Cordierite has started to alter to "Pinite", which is used to be a valid species, but it defined now as either some kind of mica or clay group minerals pseudomorphing after aluminosilicate species, especially cordierite, nepheline, topaz, andalusite, spodumene, feldspars and scapolite according to mindat.org. A really cool locality specimen, virtually unseen on the market today.
From the worldwide mineral collection of Albert Lewis Kidwell (January 1, 1919 - August 16, 2008). Al was a well-known mineral collector and research geologist with Carter Oil Company and later Exxon Oil Company in Houston, Texas. The phosphate species Kidwellite was named in his honor in 1974.