I bet you thought that nothing could get more natural than a stick of cinnamon. Wrong. Even cinnamon can be decieving. One way to tell pure cinnamon is by the price. Real cinnamon is more expensive than what you are used to seeing in the grocery store. It is almost impossible to tell by looking at different types of ground cinnamon which one is genuine and which one is an imposter. Manufacturers are not required to stipulate the scientific names of spices so reading the label is of little help. Here is the only proven way that you can tell the difference in cinnamon.
True Cinnamon – Cinnamomum zeylanicum or Cinnamomum Verumis also called Ceylon cinnamon. It comes from Sri Lanka and is harvested from the inner bark of the tree. If you live in Great Britain, it’s likely that you have been using ‘true’ cinnamon which is said to be sweeter and have a more subtle taste. Fresh cinnamon sticks are thin with several layers. The roll up from one side only, similar to a cigar. Fine and easily crushed, they are far lighter in color.
Counterfeit Cinnamon – Cinnamomum cassia or Chinese cinnamon or Cassia cinnamon comes from an altogether different plant that Ceylon cinnamon. The flavor is less delicate and it is far cheaper to purchase. Technically, cassia can still be considered cinnamon because it belongs to the same family of trees as Ceylon. A culinary master can tell you that Ceylon cinnamon is the ‘real stuff’ and cassia is imitation. The Cassia cinnamon sticks roll up from both sides and meet in the middle, similar to a scroll. They are much firmer and harder than real cinnamon sticks. Almost impossible to grind, they have a darker brown-reddish tint.
Most Americans have been raised on Cassia cinnamon and have never known it. However, this type does contain a toxin that can be harmful to the liver when consumed in large doses. Coumarin is a sweet-smelling chemical that is naturally found in cassia. It’s even been used as an additive to perfumes and pipe tobacco to improve the scent. Unless you smother everything that you eat in Cassia cinnamon, you probably have no worries. But it is nice to know that you do have a choice. Look for Ceylon cinnamon is you want the real and healthy variety.
Excerpts from: http://www.theprairiehomestead.com/2013/11/will-the-real-cinnamon-please-stand-up.html