An Etymological Dictionary of the German Language/Annotated/Zink
Zink, neuter and masculine, ‘zinc,’ Modern High German only; certainly connected with Zinn. It has been thought that Zinn, ‘tin,’ when borrowed by Slavonic was extended by a Slavonic suffix k, with which as zink it passed again into German (whence French zinc). Other etymologists assume a connection with the following word, because tin when melting forms spikes (Zinken).