This is a large and mostly complete crystal for the species from the Trona mines in Green River, Wyoming. Searlesite is an uncommon sodium borosilicate and even more rare as good crystals like this and it's a relatively attractive specimen from a state which frankly doesn't produce much in the way of great mineral specimens. It's a lustrous, tan colored, tabular crystal that shows at least four of its monoclinic faces. A truly significant crystal of a species we rarely see available. Ex. Wouter Van Tichelen collection.