Wise is correct, there are minor to trace amounts of vanadium, plenty of chromium and iron. Chemistry is close to that of Brazil and Zambian.
Due to the substantial Fe, it does not have red or pink reaction under Chelsea. Microscopy shows blocky to stretched 2 phase inclusions like Brazilian, but Brazilian emerald has unique spectrum.
There are ways to determine COO, but it takes 3 rather high tech machines and experience, however, a well seasoned emerald dealer will have insight.