German Silver is an alloy of copper, nickel and zinc. It is composed of 60% copper, 20% nickel and 20% zinc. Due to its white-silverish appearance it is named as german silver but it contains no silver in it.
1, 2, 5 are figures that have patterns formed from four lines curved in a concave direction. 3, 7, 8 are figures that have patterns formed from four lines curved in a convex direction. 4, 6, 9 are figures that have patterns formed from these straight lines.