Twelve Stone Flagons, Ltd Blended Scotch

I have a 750 ml 86 proof bottle of imported blened scotch whiskey "USQUAEBACH" by Twelve stone Flagons, Ltd. Blended & Bottled by Douglas Luing & Co., Ltd, Glasgow, Scotland. It is in a ceramic bottle with the original cork and seal in place and a second cork for use once the bottle is open. It comes in a red velvet box. I have had it for 30 years and understand the prior owner had it for many, many years. I'm guessing it is a least 50 years old if not older. Can you tell me if it is still good, value of it today and can it be drunk today? Is there a way for me to determine how old it is by looking at it?

How long is the Usquaebach "old-rare" blened whiskey in the flagon aged? does anyone know?
rich

[Dale]

I believe the Flagons is based on a 20 year (though doesn't have an age statement). Usquaebach also bottles a 15 year and a non age statement cheaper whisky (cheaper than the 15 year and Flagons). The bottling was reintroduced to the New York market in 2009. The 750ml size indicates the bottle in question was bottled for the U.S. market; the company who now owns the brand, 12 Stone Flagons, bought the brand in 1973 so the bottle in question isn't older than that. Here's a good history of the brand:

http://www.whatdoesjohnknow.com/2009...n-circulation/