What this coin looks like (obverse, reverse, mint mark location, special features, etc.):
One major variety of the 1873 Liberty Head $2.50 Gold Quarter Eagle features the Closed "3" in the date. This variety features a slightly different style of the number "3" in the 1873 date. The Closed 3 has much less spacing between the top and bottom arcs on the left side of the three. The Open "3" has much more spacing between these features within the "3". The difference between the Open 3 vs Closed 3 $2.50 gold quarter eagle is depicted below in the example comparison image:
Coin valuation chart: Typical coin prices, values and worth per grade or condition - in USD