Ludlamite on Siderite

Ludlamite is a rare iron-manganese-magnesium phosphate which was first described from Wheal Jane in Cornwall in 1877.  Although magnificent crystals have been known since this first discovery, the deposits at the Cabeça do Cachorro Claim in north-western Brazil have set new standards, if only for the abundance of Ludlamite crystals found within the phosphatic nodules.  The specimens are recovered from alluvial deposits along the Cauaburi river which runs through the Pico da Neblina National Park.  This wonderful specimen has a long chocolate-brown Sideritic matrix, the surface of which is totally encrusted with micro-crystals of dark chocolate-brown Siderite over which about 90 to 100 superb Ludlamite crystals are scattered.  These are gemmy to translucent and range from deep leaf to light apple-green with a bright, highly reflective glassy lustre.  The crystals mainly occur as individuals, although sometimes as small clusters and frequently attain between an impressive 1 and 1.6 cm.  Many crystals form asymmetric narrowing towers, commonly termed ‘Tower of Babel’ habit.  A delightful museum-quality (and sized) Ludlamite from Amazonas, Brazil.