[bombcar]

A water jet sends an extremely high pressure thin jet of water that can precisely cut many materials.

https://en.m.wikipedia.org/wiki/Water_jet_cutter

[namdnay]

water + an abrasive in this case, water won't cut an iphone

[hoseja]

The water is filled with sapphires.

[daniel_reetz]

Actually, the abrasive is garnet, but the orifice that forms the jet is a drilled sapphire.

Source: I own and operate a waterjet.