Gold Coins vs Gold Bars
Neither format is universally better. The useful comparison is the exact product's premium, liquidity, unit size and intended use.
Coins
Widely recognized bullion coins can be available in smaller units, which may make partial liquidation easier. Premiums can vary by mint, size and market demand.
Bars
Bars are available across a wide range of sizes and may have different premium economics. Larger bars can be less divisible when an owner wants to sell only part of a position.
IRA buyers have another filter
Product format alone does not establish IRA eligibility. Verify the exact coin or bullion item against the federal rules and the receiving custodian's procedures.