What is Aureus?
An aureus is a gold coin issued from the 1st to the 4th century BC in ancient Rome. The word “aureus” itself means gold in Roman and this particular coin is considered rare and precious for gold coin collectors. It was said that no other than Julius Caesar ordered for the aureus’ use for general circulation after this gold coin was first used in big transactions only. The value of the aureus gold coin is equivalent to 25 pieces of the silver coin called denarius. Its size and shape is similar to that of the denarius but is significantly much heavier owing to its much-heavier gold component.

Over time, the gold component and the overall weight of the aureus was reduced. Under the regime of Emperor Julius Caesar, the aureus gold coin weighs about 8 grams with 99% gold composition. By the time Nero reigned, less gold was put in making the coin lowering its weight to around 7.7 grams. Years passed and when Caracalla became the Roman emperor, the aureus gold coin only weighed 1/50th of a pound or only 6.5 grams. Later on, the aureus gold coin was replaced by another coin called “solidus” and this one weighed only 4.5 grams.

But even if the weight of the aureus gold coin was decreased over time, the purity of the gold remained somewhat consistent. And because of the inflation in the Roman Empire wherein only silver and gold coins were accepted for tax payments, the value of the aureus when compared with the denarius also grew significantly. In the year 301 AD, one aureus gold coin was worth more than 833 silver denarii. Some 20 years later, this same gold coin had a value of 4,350 silver denarii. By the year 309 AD, the aureus gold coin was replaced by the larger but flatter solidus coin. This happened at the time when Constantine ruled the Roman Empire.