Desk seal with the coat of arms of the Chertkov family Second half of the 19th century Rutilated quartz. Height 63 mm The type of mineral from which this seal was made is known as Venus hairstone. It is clear quartz containing yellow-golden hair-like crystals. The fashion for making seals that imprinted the family arms or a monogram while also serving as a desk ornament was particularly strong in Russia in the second half of the 19th century. The "preforms" for such seals - in the form of vases, animal figures, little columns and so on - were produced by Yekaterinburg craftsmen and the image for the matrix was engraved to the customer's order. The craftsmen tried to choose the most interesting, at times bizarre pieces of stone for their works. The Chertkov seal is double-sided: the lower matrix is for the coat of arms granted to the family in 1794, the upper one for the surname.