In Finland, the state has the right to mint coins, which are issued by the Bank of Finland. Coins that are seriously damaged may not be used as legal tender, nor do they need to be accepted for payment. The Bank of Finland is obliged to accept damaged coins if their authenticity can be verified.
Under Article 8 of Regulation (EU) No 1210/2010 of the European Parliament and of the Council, the Bank of Finland may refuse reimbursement of euro coins unfit for circulation which have been altered either deliberately or by a process that could be reasonably expected to have the effect of altering them. Such procedures where coins are exposed to damage include their destruction by crushing, burning or other similar means. The Bank of Finland may unilaterally decide, case by case, whether to redeem damaged coins.
Private persons may return damaged coins to their own banks. The coins must be packed by denomination in bags or boxes. The bag or box must be accompanied by an overview of the contents (a form for damaged coins), indicating the sender’s identifying details, the denominations and quantities of the coins and an explanation of what has happened to them. You can get more detailed instructions from your own bank.