I have a Gold ring 18k, with a 3/4 - 1 carat Ruby on a very high setting, that was?

given to me by my late grandfather. I have never ever saw my grandfather wear this ring, as its very femine looking and much to fragile to wear. I was told when it was given to me that the ruby was genuine, and of considerable value..Right now! it does NOTHING for me but sit there and collect dust. I sure could use the money value of this ring instead of just letting it sit there, and I'm sure my grandfather would agree. However, my Father (his father), who is now deceased himself, would regard this selling of an heirlooms ,sacrilegious, and probably would be extremely angry ..I'm a sentimental guy, but not with those type of items. When does the value of an heirloom like this do anyone any good?