There is no trustless way to determine if some coins are only dormant or truely lost. Provably lost coins are non-zero outputs of OP_RETURN or other provably not satisfiable redeem scripts and not fully claimed coinbase amounts (I may have missed other truely provably burned coins).
There were also coins that were lost due to the coinbase transactions having the same hash.
The coins claimed by miners in blocks number 91722 and 91812 are unspendable.
The coinbase transaction in block number
91722 has the same hash as coinbase transaction in block number
91880 and the coinbase transaction in block number
91812 has the same hash as coinbase transaction in block number
91842.