Titanite ("Sphene") ("trilling" twin) (ex Kay Robertson Collection)

Item Description

The Austrian Alps are the source for the finest Titanite crystals in Europe. They are beloved by Alpine collectors for their excellent quality, color and beautiful morphology. This piece is labeled only as coming from the Untersulzbachtal (Untersulzbach Valley), but there are literally many dozens if not hundreds of localities for Titanite around Salzburg and the Tyrol, so it's hard to say specifically where this one is from. It should be noted that this piece is labeled as "Sphene", which is an archaic synonym for Titanite, but not a varietal term. With that said, you see more of these correctly labeled as Titanite these days. This piece features many sharp, well-formed, lustrous, "wedge"-shaped bladed crystals of Titanite which have a coating of semi-metallic, sparkling "Chlorite" (most likely Clinochlore) sitting on a thin slab of matrix. There a loads of crystals on both sides of the specimen, and virtually all of them are pristine. With backlighting, you can see the color in the larger crystals is a beautiful green hue, while the smaller Titanites show more of a golden-yellow color. The largest crystal on the specimen is actually a beautiful "trilling" twin, which measures 2.2 cm. The broader side of the twin plays host to the smaller secondary crystal, creating a three-pointed twin, that is indicative of this material. A highly desirable, fine quality and eye-catching specimen of this historic material from Austria. Valued at $500. Ex Kay Robertson Collection (#11190). Kay was a prominent California collector, who specialized in European classics. She nearly lived 100 years from April 1920 - March 2020. See the article in the March-April, 2007 Mineralogical Record ( https://www.mineralogicalrecord.com/pdfs/Kay%20Robertson%20Collection.pdf ), and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017.