What are 1905 two and half dollar gold coins worth?

In circulated condition, they're worth $150-$175

Most uncirculated ones are worth $200-$400

A real nice uncirculated one is worth over $1,000 but you need to have it professionally graded.

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The type of coin minted is the 1905 Indian Head $2.50 Gold Quarter Eagle. It was only minted in Philadelphia and according to USA Coin Book, the value of this coin in Very Fine condition is about $180 up to about $350 in MS60 mint condition. An MS63 Choice uncirculated coin is worth about $980. Proof coins were also minted here and those are worth about $6,500 in PR63 choice proof condition, if you are lucky enough to find one.

As of 10/2010, the gold content of this coin is worth about $170.