We've been given an old bottle of alcohol, an amaretto.
At the top of the bottle, where the lid and bottle rim meet, a few crystals have formed. I'm guessing it's the sugars but am not sure.
Some one has mentioned they think the crystals forming means you should throw the bottle (and contents) away as it's not safe, but I can find no proof of this online.
Does the forming of the crystals indicate the drink is no longer safe?