Groote Eylandt Mining Company Pty Ltd (commonly known as GEMCO) is a mobile network operator in Australia assigned PLMN code 505-42 by the national telecommunications authority.

The MCC 505 identifies Australia, while MNC 42 uniquely identifies this operator within the country. Together they form the PLMN (Public Land Mobile Network) identifier used by mobile devices for network selection, SIM card identification, and international roaming.

This assignment was last reported in ITU Operational Bulletin #1280 (Nov. 15, 2023). Search all MCC/MNC codes or view all Australia operators .