Originally Posted by Anateus
Please stop trolling/making yourself look like a fool on purpose.
You either skipped physics in your school or can't accept the truth.
Coins and keys will never scratch your phone unless they're made of steel. They will help scratch your phone in your pocket if there is sand in there already. But not on their own.
Originally Posted by ghostrider85
Yeah, sand can scratch your screen, not some change or keys.
How about this? Someone asserting that they will scratch demonstrate it on camera (these scratches are easily seen under reflection of bright light). If it scratches, one of you nonbelievers either do a complete replacement of the glass (with included 1-day shipping both ways, paid by you), or buy a same new device outright for the person who demonstrated it.
No excuses are to be made whether it's a scratch of the glass or not. If it can't be wiped clean with cloth and water alone (i.e. the scratch line remains under reflections of light), it's a scratch.
You are entirely discounting the fact that these crystals can get attached/embedded to surfaces of coins and keys, from handling alone.