An Etymological Dictionary of the German Language/Annotated/Schatz
Schatz, masculine, ‘treasure, store; sweetheart,’ from Middle High German schaz (genitive -tzes), Old High German scaz, masculine; its chief senses down to the 13th century are ‘money, property, wealth,’ and only later ‘valuables stored up’; Old High German scaz, masculine, is only ‘money, a definite coin.’ Compare Gothic skatts, ‘coin, money,’ Old Icelandic skattr, ‘tax, tribute,’ Anglo-Saxon sčęatt, ‘a certain small coin, money, property,’ Old Frisian sket, ‘money, cattle,’ Old Saxon scat, ‘piece of money, property.’ The early history of the cognates is unfortunately too obscure; opinions are divided whether the Teutonic word shatta- is derived from Old Slovenian skotŭ, ‘cattle,’ or whether the latter comes from Teutonic. The variation in meaning, ‘cattle’ and ‘money,’ is analogous to Latin pecunia from pecus, English fee from Anglo-Saxon feoh, ‘cattle’ (see Vieh); in bartering, cattle played the part of money. Yet we cannot prove that the primary meaning of Old Teutonic *skatta-, ‘money, coin,’ is ‘cattle.’ On the other land, the assumption that the word is primitively allied to Greek σχέδη, ‘board, tablet,’ is certainly not satisfactory on account of the meanings of the Teutonic words.