A custodian is required for a precious metal IRA because the Internal Revenue Service (IRS) regulations state that all self-directed IRAs, including precious metal IRAs, must be held with a custodian. The role of the custodian is to oversee the management and administration of the IRA, ensuring that all transactions and investments meet the IRS rules and regulations. The custodian is also responsible for holding the precious metal and ensuring that they are stored in an IRS-approved depository. This helps to ensure the safety and security of the assets in the IRA.