Coins can be generic or collectible. Generic coins are often known as “rounds.” Collectible coins are often called “numismatic” coins, a hobbyist term based on the Latin word “numisma” for coin.
Now most old school economists would claim that gold is not really a credible investment because it only has intrinsic value. Not in these days, if what was considered unthinkable happens and the dollar continues to decline in value, and as other countries agree to replace the dollar with another trading currency, gold will become the trading instrument of choice around the globe. That is not as farfetched as it sounds.