This is a world class, INCREDIBLY RICH specimen for the species that hsould be categorized as about the ultimate a collector could obtain for both quality and size, with overall significance corresponding to the combination of those traits. It is a beautiful plate from the mid-1800s in all likelihood, with shrp crystals of 3 distinct crystal habits for the species, all perched in isolated clusters on contrasting quartz matrix. The largest cluster is 4 cm tip to tip, with the sharp spear sticking out the top. It could actually be brightened up quite a bit, but I liked the antique look and have not treated the piece to enhance its luster (both the quartz and the hessite should come up a bit). This specimen was owned by BOTH MAJOR collectors of Austrian minerals at the turn of the century in the late 1800s and early 1900s, Berger and Metzger, spanning the world wars in their care. Anton Metzger was a dealer and collector knwon for fine taste, who specialized in the minerals of the Austro-Hungarian Empire. His handwritten label dates the piece to his ownership prior to 1929, according to the archives at the above link. Most of the collection of Anton berger was absorbed into the Metzger collection, and in turn passed on to the Schwethelm collection in later years (though I cannot say if this piece went that last route for sure, I suspect it is the case). Additional history on this specimen will be given to the buyer - it is from a major and very private, US collection.