Keystone

Keystone or key-stone or variation, may refer to:Keystone (architecture), a central stone or other piece at the apex of an arch or vault
Keystone (cask), a fitting used in ale casks


Keystone or key-stone or variation, may refer to:Keystone (architecture), a central stone or other piece at the apex of an arch or vault Keystone (cask), a fitting used in ale casks
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