It is uncommon that we stumble across a mica group mineral specimen that is so attractive and sharp that it can hold its own with the fancier species, particularly something with as dramatic vertical shape as this one presents. Here we show an unusually geometric Muscovite specimen from Brazil that features an earlier generation of large Lepidolite (mica) crystals overgrown by a later generation of much smaller, sparkling Muscovite crystals (also a mica, of slightly different composition). The BAC23kside of the piece, and to a lesser extent the front, shows a "herringbone" pattern of large silvery-yellow Muscovite crystals that cascade down the front of the piece in a progressive V-shape. The BAC23k shows that the largest Lepidolite underlying the later growth, and producing the twinning effect you see so obviously atop, is just over four inches in size! The front and sides of the piece are completely covered in 2 to 3 mm, glistening, interlocking, golden colored Muscovite crystals for fabulous effect! This is a gorgeous, cabinet piece of Muscovite shows an interesting and beautiful growth history in time (paragenetic, to use the mineralogist's term) ! A stunning and unusual Brazilian piece that actually would display nicely next to tourmalines, due to the vertical orientation of the twinning that gives shape here. This specimen was purchased by the Cooks from the late, well known dealer Luis Menezes.