Quartz on siderite - surroundings of Gourrama, Morocco
 
 Absolutely flawless, water-clear, 4 cm quartz crystal with an excellent luster on siderite. The transparency and clear crystal shape of the quartz form a special contrast to the rough surface of the siderite. The 9.5 cm x 9 cm specimen was found at Gourrama in Morocco. Historical find from the collection of Josef Kolb.