For example, if your cinnamon has been grown and harvested in Sri Lanka, it's likely authentic. However, if the words "cassia bark" are on the label, or it mentions "Chinese cinnamon" or "Saigon ...
The bark is scraped off the tree ... and cassia cinnamon (also known as Cinnamomum cassia and Chinese cinnamon). Both types are just sold as "cinnamon" in the U.S., but Ceylon cinnamon is ...