Wow, what a beautiful coin. Your coin contains (no surprise) 37.5 grams of pure gold (oro puro), and this is where it gets its value. To figure out this value, first convert grams to Troy ounces:
37.5 grams / 31.1 grams per Troy ounce = 1.205 Troy ounces
Now look up the value of pure gold on a web site like kitco.com
gold 'spot' value today = $1407 US dollars per Troy ounce
1.205 Troy ounces x $1400 $ per Troy ounce = about $1700
Kitco reports the 'spot' value of gold, which is pure bullion value. If your coin is in excellent condition, you can add a small amount, say $20, to the value to account for the fact that the gold has been minted into a nice looking coin.
The catalogs report absolutely, fully uncirculated coins as having a premium above the gold value of about $500. Coins dated 1947 are more common in high grades and do not have this added premium. A dealer would pay you the gold spot price plus perhaps half of the premium to buy the coin from you.
The spot value of gold changes every minute. Look up the price right now! If you are buying or selling from a gold dealer, he or she will invoke a commission to handle the transaction.