What is the value of an 1861 US 20 dollar gold coin?

Answer 1

You need to know the coin's mint mark (on the reverse) and its condition. The raw gold it contains puts its minimum value about for a very worn Philadelphia issue, but in better condition and/or from another mint it could be worth much more than that. The so-called Paquet reverse (an alternate design by engraver A. Paquet) is very rare and is worth well over ,000 but it must be identified by a numismatic professional.

You can get a rough idea of prices from a site such as http://www.numismedia.com/fmv/prices/20gld/pricesgd.shtml , but a specific value would require having the coin appraised in person by a certified dealer or appraiser.