In Soviet Russian during the 1940s (and through the 1960s) pop music, and bootlegs of forbidden music were smuggled through a series of black market dealers via old X-Ray. This was because X-Rays ( and film negatives) we're available and sturdy enough to take an engraving. The spindle holes we're typically burned out with a lit cigarette. Selling these "Roentgenizdat" ( Bone or X-Ray records) or even owning them was forbidden and could result in major punishment.
For more info check out 99% invisible's podcast on them.
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