Strictly speaking these are not coins but commemorative medallions. ajs is spot-on about them having no purchasing power. They will have value as collectors items, but it is likely to be low.
By the way, a lot of people have an incorrect view of the meaning of the term "legal tender". It does not mean "can be spent in shops as money". It refers to payments for pre-existing debt, not for buying/selling in a shop and paying at the time of sale. If you buy/sell with an agreement to pay later, then it will apply as there will be a pre-existing debt when payment becomes due.
You can pay in shops or pay off a debt using anything you like, as long as the other party is happy to accept what is offered. If you offer to pay a debt using something that is not legal tender the other party can refuse to accept it and still sue you for payment because the debt still stands. If you offer to pay a debt using legal tender and this is refused, you cannot then be sued as you have offered to discharge the debt.
What is legal tender varies from place to place. In the UK Bank of England banknotes are legal tender along with coins of £1 and above. Smaller value coins vary as legal tender according to the size of the debt. For example, if somebody chooses to pay off a debt with a van-load of pennies as a protest, this can be refused and the debt would still stand as pennies and tuppences are only legal tender for debt up to 20p. Bank of Scotland banknotes are not legal tender, but are widely accepted.