Minecraft wiki entry for Unused_textures, associated text: Rubies were intended to be the original currency used for trading. They could be seen in a screenshot released by Jeb on 21 May 2012,[19] in which the trading system was first being tested. While it was later decided that emeralds would take their place as a currency, a ruby texture still made its way into items.png in Java Edition 12w21a alongside that of the emerald. The unused ruby texture which was present in the game differed from the version shown in the screenshot, however; both versions of the texture are shown below for the sake of comparison.