Barn find advice

[Dan the man]

Greetings all. I’ve come across 2 boxes of miniature Whisky’s all 70% proof and all ages before 1970! Is there much of a market for selling or am I better off sitting back, relaxing and supping away?
Thanks in advance
Dan
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Hey up

[James T]

Depends on the whisky, what whisky is it and are the bottles in good condition?

[arqueturus]

When you say 70 proof...?

I may be wrong here but wouldn't that put them at 35% ABV? Which is a lower ABV than what is currently allowed to be deemed Whisky (assuming Scotch here).

Basically, need more detail.

[MattS]

Likely the old proof numbers when 70 proof = 40% abv

https://en.wikipedia.org/wiki/Alcohol_proof

By the end of the 17th century England had introduced tests based on specific gravity for defining proof. However, it was not until 1816 that a legal standard based on specific density was defined in England. 100 proof was defined as a spirit with ​12⁄13 the specific gravity of pure water at the same temperature.[4] From the 19th century until 1 January 1980, the UK officially measured alcohol content by proof spirit, defined as spirit with a gravity of ​12⁄13 that of water, or 923 kg/m3, and equivalent to 57.15% ABV.[5]

The value 57.15% is very close to the fraction ​4⁄7 ≈ 0.5714. This led to the definition that 100 proof spirit has an ABV of ​4⁄7. From this it follows that, to convert the ABV expressed as a percentage to degrees proof, it is only necessary to multiply the ABV by ​7⁄4 . Thus pure 100% alcohol will have 100×(​7⁄4) = 175 proof, and a spirit containing 40% ABV will have 40×(​7⁄4) = 70° proof.