The first image is of an 18k pendant / enhancer with a Tanzanite center. The bail at top can clip onto a gold chain or a strand of pearls. This is a custom piece, made by hand and will vary each time depending on the gems used.
This one has a 1.8ct Tanzanite at the center, 35 pts in VS diamonds, and 4 intense green 10mm Tahitian pearls. It measures around 1 & 3/4" high x 1 & 3/8" wide.
Other available stones are pink or green tourmaline, as well as a variety of pearls.
Each piece is custom made and prices depend on the gems used. A heavy gold chain or a pearl strand can also be purchased. Or a combination of the 2, a chain w pearls spaced throughout.