Hardness of imitation pearl?

[nbadream178]

I know that moh's hardness of cultured pearl is 2.5-4.5
How about the hardness of different type of imitation pearl(plastic and glass)?
I want to distinguish the imitation pearl by moh's hardness test.

 

[jshepherd]

Plastic would be softer than a pearl and glass harder. You can scratch a pearl with glass, but you shouldn't be able to with typical plastic. I believe glass is around 5 on Mohs scale.

 

[pattye]

Imitation pearls, no matter if the center is glass or plastic, is coated with layers of resin or paint giving the pearl-like look, and that can be scratched.

 

[Pearl Dreams]

High quality imitations like Majorica brand are a bit more more scratch resistant than real pearls.

But there are better ways to tell imitation pearls from real ones.