Comparative Hearts oddities This listing is for one

This listing is for one small irregularly shaped Australian opal electroformed and strung on a 16" or 18" sterling silver ball chain

This jewelry is unique and one-of-a-kind

Produced since 1917

A temperature of 1800 degrees Celsius is required to instantaneously melt sand and form a fulgurite

Citrine is just one of those minerals that should be in every collection

Comparative Hearts oddities This listing is for oneFinally. An easy and convenient way to compare hearts! Hearts included: Fish, Amphibian, Reptile, bird, and mammal. It allows you to see in detail the structures of the heart and similarities and differences between different animal types. These specimens are set in transparent lucite resin. It's truly a unique and interesting way to study the inner workings of arguably the most important muscle of any living creature. Plus, they make a great