I think the cube cut is the most rare version and quite scarce to come by,
a while back there was a dood on eBay tring to sell a tin exactly like yours for $900!!!!
http://pipesmagazine.com/forums/topic/is-this-vintage-tin-worth-it
8O
I think it's the same as flake, just with the different cut, it most likely has fared very well in the screwtop tin and you will be amazed by the intense aroma when you open it!
I had a couple of tins of the flake from the same era...
...and the flakes were dark 'n lovely, and the scent was powerful. It's definitely a love/hate type of flavor.
The typo on the distribution stickers is sorta funny, I guess they didn't mind too much and used 'em anyway.
Your tin is most definitely pre-1974 because that's when House of Edgeworth was closed,
so at minimum it's 40 years old!
Good score!
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