Siderite   Hogarth Pit, Steep Rock Mine, Atikokan, Ontario, Canada.  This is an attractive, curtain like plate of crystals measuring 7.8 x 4 cm.  In most places it is less than half a centimeter thick.  The entire piece is coated by tiny siderite rhombs.  Only contact area is one edge in a tiny part of the base.  Very showy.  $30