Vintage Sparkling Blue Art Deco Czech Glass Brooch

Large blue glass stones are secured with four prongs. Stones are faceted to shine and sparkle in the light. Small stones are clear with some being darker than others. On the back, there is a square that might have had a signature or brand, but it has been rubbed off. The stick is still very sharp and is fastened underneath a  curved hook. I do not see any missing stones which is unusual for a brooch this old. Approximate measurements are- 2.5 inches across longest width and 1.75 inches across longest height. They don’t make brooches like this anymore. So well made!