10 Korun Československých

Tuzex was a Czechoslovak state-run retail chain that operated on a parallel currency system — ordinary citizens could use Tuzex bony (vouchers) to purchase Western goods unavailable through standard socialist retail channels. The bony themselves functioned as a hard-currency proxy, convertible from foreign exchange at official Tuzex counters. This created a two-tier economy in miniature: those with access to Western remittances or foreign contacts could obtain consumer goods the koruna simply could not buy.

The 10 Kčs denomination sat at a practically useful mid-range within the bony series. By the early 1970s a secondary black market in the vouchers was well established, which the state tolerated as a pressure valve — and taxed indirectly by controlling the conversion rates.