Diana and Artemis were two sides of the same goddess-- different names for the same maiden goddess and twin sister of Zeus, or Jupiter.
Diana, her Roman name, and Artemis, her Greek name, was known as the Lady of Wild Things and was consistently associated with animals and all nature. Diana/Artemis embodied the untamable-- sometimes depicted as vengeful and violent, other times as compassionate and sparing to mortal women in particular.
Historically, Diana/Artemis has been associated with Selene, the goddess of the moon and later went on to represent the moon goddess.
The progression of her narrative-- the goddess of huntsman and wilderness -- is rife with contrast of acts of good and those of evil. These two one-of-a-kind Cameo necklaces are vastly different and encompass her dueling nature and names.
Sources:
Mythology by Edith Hamilton
The Iliad by Homer