Old Grand-Dad Kentucky Bourbon

Old Grand-Dad: made 1970, bottled 1976

I have been passed down this bottle via my wife’s family. It was bottled the year she was born and her dad (estranged) had some story as to why he has it and gave it to us maybe a decade ago or more. There was some bad family mojo surrounding it so he offloaded it as there was a reason he never opened it, etc.

So I’ve done a bit of searching and know it’s kind of special but not overly rare. It’s been in the family since 1976 and is 1 quart, 100 proof, bottled in bond. Trying to figure out if it’s worth keeping, drinking, or selling. I’ve been a bit of a bourbon fan and delved into Irish and Scottish whiskey over the years and go back and forth (mostly wine drinkers but we both like a whisky once in a while).

Attached are some pics of the bottle with the seal. Any advice or recommendations appreciated as well as a valuation. Has been stored out of sunlight and in a liquor cabinet for the 20 years or so that I’ve been aware of its existence. Thanks!