It depends, but there is a high probabilty that it will decompose because of the presence of anaerobic microorganisms (bacteria which thrive under the absence of air / oxygene) and of mould. In the US, many metal caskets and vaults are hermetically sealed (air and water tight).
Chat with our AI personalities
Probably yes because of the presence of anaerobic microorganism (bacteria thriving without oxygen) and of mould.