Vtg Silver Tone Diamond Shape Brooch Turquoise Aurora Borealis Gem Stone Art Pin. Pronged gemstones 9 Large Round Turquoise Aqua colored Gemstones with a outline of smaller Aurora Borealis type turquoise and blue gemstones. I think there are 52 gemstones in total. Might be Czech glass?????? Very pretty diamond shaped brooch that can be worn vertically and horizontally. Silver tone backing with no markings. Unsigned. Clasp works as intended. Approx 2 1/4" X 1 3/4". Very good condition - no flaws detected - all gems intact, no scratches or chips that I can detect with the naked eye. See all pics and zoom in for details.