I gave my phone to my aunt to look at some pictures.  She had a diamond crusted ring on her right index finger.  Scratched the screen when she swiped... I'm mad, but, I only can see it when the screen is off and the light shines a certain way.  That's diamond, one of the hardest objects on earth.  I do believe this screen is resistant to most other objects, such as coins, keys, and other metals.
				
			
	