Amber was one of the first substances used by man for decoration, and it was ... employed at a very early period for amulets and for medicinal purposes. More or less shapeless pieces of rough amber, marked with circular depressions, have been found in Prussia, Schleswig-Holstein, and Denmark, in deposits of the Stone Age. These depressions are sometimes regularly disposed and at other times irregularly, and seem intended to imitate similar depressions found in large stones and rocks, often the work of man's hand, but occasionally the result of natural causes. In Hoernes' opinion they marked the resting place of the spirit or spirits believed to animate the stone, and hence it is probable that the amber fragments were used as talismans or amulets. (Hoernes, "Urgeschichte der bildenden Kunst," Vienna, 1898. Figured in S. Muller's "Ordn.