These are real nephrite jade pendants which are a beautiful green colour with black inclusions. They represent a version of jade that has a waxy feel called nephrite. The term jade is based on geological terms and requires a microscope to see the structure. There is heaps of “jade” out there which are actually serpentine, jasper, chrysoprase and aventurine.
There is a drilled hole that may fit some silver chains with narrow ends, but leather is the more typical cord. Most people also buy them for their “good luck” healing properties.
Enjoy the heart supporting and expanding abilities with a green nephrite jade pendant. Discount is to help them find forever homes. They all look nearly the same so will intuit one from stock for you.