Blue looks good on everyone and this lovely emerald cut, rectangular aquamarine will be your everyday necklace. Set in a 18k cage with a prong setting the aquamarine almost seems like it is floating. Paired with an oval 18k cable chain.
Second photo shows back of necklace.
Aqua measures 20mm wide and 11mm tall (approximately 3/4"x1/2") Chain measures 16.5 inches long.