CALOMEL with NATIVE MERCURY

SPECIMEN DESCRIPTION

An excellent miniature of the rare mercury chloride, Calomel, together with Native Mercury, from the ancient mercury mining district of Landsberg in Rhineland-Palatinate, Germany, south-west of Frankfurt am Main. Moschellandsberg hill (now shortened to Landsberg), is within a region rich in mercury and mercury minerals, where mining began in around 1440. Because of mercury's unique property of being the only liquid metal at ambient conditions, it has been known since ancient times, and is thought to have been first discovered by the Ancient Egyptians, prior to 1,500 BCE. The Calomel forms several well developed, smoky grey crystals, the largest nicely developed to about 3 mm. Bright silver micro-globules of liquid metallic Native Mercury are scattered over a grey surface coating together with probable, micro-crystals of Tetrahedrite. The Native Mercury will vary in the amount visible due to thermal expansion and contraction, according to the ambient temperature. Such liquid mercury does not readily detach from such specimens due to the strong capillary pressure between it and the rock pores from which it emanates. An old handwritten label, numbered 2148, is glued to the front of the specimen, but well clear of the mineralized area. This label is from the collection of Joseph Neeld (1789-1856). This is a superb example of Calomel. For any specimens containing mercury and or mercury bearing minerals, it is a sensible precaution to always wash your hands after handling.