Library note
Mint authority and freeze authority, read in that order
The mint account tells you who may create more of a token and who may freeze a holder's token account. Those two authorities are not the owner of your balance.
The mint is a separate account
A mint account stores supply, decimals, a mint authority, and a freeze authority. Your token account stores how much of that mint you hold, and in what state. Mixing the two accounts is the most common mix-up we see on Saturday mornings. A holder does not become the mint authority by holding a balance.
Decimals explain the supply figure. A supply number without decimals is not yet a quantity a treasurer can enter in a book. We write both before we talk about anyone's wallet.
Mint authority
When mint authority is set, that address may mint new supply, subject to the instruction rules. When the authority has been removed, further minting through that field stops. Readers like a simple promise here. We keep the sentence narrow: look at the field as it stands today, and write whether an address is present.
A club that receives a token as payment should know if supply can still increase. That fact does not tell them the price. It tells them whether the issuer still holds the pen.
Freeze authority
Freeze authority, when set on the mint, may freeze a token account of that mint. A frozen token account stays in place, amount included, and transfers do not proceed until a thaw. The owner's signature does not override a freeze. That surprises people who think possession of the wallet is the whole story.
If the freeze authority field is empty, note that too. Absence is a reading, not a blank you skip. In Geumsan we have sat with a cooperative treasurer who only needed this one line: the freeze authority was still an address she did not control. The rest of her map could wait until Monday.