Ross-Simons - 3.00 ct. t. w. Diamond Tennis Necklace in Sterling Silver. 16". This 3.00 ct. t. w. round brilliant-cut diamond tennis necklace is a style essential for the avid diamond lover! Dress it up or dress it down - this piece looks great on-duty or off. Shines in polished sterling silver. Graduates from 1/16" to 3/16" wide. Single-latch safety. Push-button clasp, diamond tennis necklace. Diamond birthstones are the perfect gift for April birthdays.