Denarius

The denarius was a small silver coin used by the Roman Empire and Roman Republic. The denarius weighed about 3 to 4.5 grams. It was the main coin of Ancient Rome. It became the most common coin produced for circulation but was slowly debased in weight and silver content. The coin was then sometimes made of copper and painted silver in color. During the Empire the front side usually had a picture of the emperor on it.

row 1 : 157 BC Roman Republic, 73 AD Vespasian, 161 AD Marcus Aurelius, 194 AD Septimius Severus;
row 2: 199 AD Caracalla, 200 AD Julia Domna, 219 AD Elagabalus, 236 AD Maximinus Thrax.

The denarius was introduced in 211 BC, and was last made in 275 AD. By then it was made of bronze.