Nether ice
Nether ice was a major export from the planet Neftali.[1] It was mined from Neftali's ice fields and could remain in a frozen state for a long period of time due to unusual compounds in its structure. Small pieces of nether ice could remain frozen for up to a month, and smugglers had been known to use nether ice to cool engines during emergencies. Although generally sold in bulk, nether ice could be bought as souvenirs and even customized into jewelry.[2]