Model Number: GS 51-GS 55B Gold Testing Stone Brand Name: GREEN STARS SA Key Specifications/Special Features: Gold testing stone, jewelry tools, gold testing stone jewellery toolsGold testing stone:GS 51: gold testing black stone 2 1/2 x 1 1/2x 1/2"GS 52: gold testing black stone 3 x 2 x 1/2"GS 53: gold testing black stone 4 x 2 x 1/2"

GS 54: gold testing black stone 6 x 3 x 1/2"

GS 55: gold testing black stone 8 x 3 x 1/2"

GS 55A: gold testing black stone 6 x 4 x 1/2”

GS 55B: gold testing black stone 16 x 3 x 1/2”