important German writer on early metallurgy.

Ercker studied at the University of Wittenberg (1547–48) and in 1554 was appointed assayer at Dresden, the first of many such positions he held in the state bureaucracy of Saxony. After 1567 he became control tester of coins at Kutná Hora, near Prague. In his great work, Beschreibung allerfürnemisten mineralischen Ertzt und Berckwercksarten (1574; “Description of Leading Ore Processing and Mining Methods”), he presented a systematic review of the techniques then in use for testing alloys and minerals of silver, gold, copper, antimony, mercury, bismuth, and lead; of obtaining and refining such metals; and of extracting acids, salts, and other compounds. It may be regarded as the first manual of analytic and metallurgical chemistry.