(Hint: don't throw it away!)
It means CONGRATS you now have two crystals!
But really... Some stones are softer than others and can be damaged easily when exposed to heat or stored improperly.
Some people believe crystals break because they've absorbed a large hit of negative energy (and dropping it on the floor doesn't count). This ring suddenly broke cleanly into two pieces without any prior, visible signs of damage.
If a crystal breaks, we encourage you to cleanse it and keep it so it can continue serving you in its new format. You could also gift the new piece to someone else. However, if you decide it no longer serves you, please place it back into the Earth. Bonus: your indoor houseplants would LOVE the cleansed energy of a fragmented stone!
Looks like you haven't made a choice yet.