Turquoise? Bangle

Cold to touch but can’t tell for sure if natural turquoise. What do you think?

 

It looks like dyed magnesite, if it's stone. Maybe howlite, but odds on magnesite.

 

I see white patches on few places so indeed it could be dyed magnesite.
I rubbed it with nail polish remover containing acetone but nothing came out. Maybe I need stronger solution. Or it’s not necessary the dye to come out?

 

I remember reading that dyed Howlite is coated with either a resin or acrylic so the color will not bleed.

 

So, hot needle should penetrate the top layer

 

I saw this necklace today, nothing special but one piece was broken so I took few photos for educational purposes.
What can we tell, dyed or not?

 

Are the 2 dark spots bubbles?If so it is probably Chinese man made mystery "turquoise".

 

Don’t know, like small holes.They look suspicious.

 

No idea what it is, except not turquoise. Some kind of composite possibly.