C. 1990. Completely classic, totally timeless. From our Estate collection, these stunning 1.80 ct. t.w. round brilliant-cut diamond stud ear… C. 1990. Completely classic, totally timeless. From our Estate collection, these stunning 1.80 ct. t.w. round brilliant-cut diamond stud earrings are a quintessential choice -- beautifully nestled within four-prong platinum settings. A pair you'll wear, and adore, now and always. Post/clutch, diamond stud earrings. Exclusive, one-of-a-kind Estate Jewelry.