I don't think anyone can say much. Looks like either a chip or a natural on some vitreous-looking "gem." Certainly will not be a major determinant of value or durability.
As a qualified expert I say you need to make better pictures
Jokes aside, what exactly are you asking? If the stone is good? That’s anyone’s guess. Is it valuable? Unlikely, but hard to tell, you need to send to a lab for proper testing if that is what you want to know. Do you see inclusions? What is the tone/saturation in daylight?
“Good” doesn’t mean much unless you give it context. I think it looks fine and would be happy with it - the small chip would not concern me.