Here is a 470.00Ct Aquamarine and Black Onyx 18" Necklace. This is part of a jewelry store stock that will be auctioned this week. If she loves cool blue Aquamarines- this is a must have. The necklace has 25 Aquamarines that measure approximately 13-14mm in diameter. In between each link is a Black Onyx. The color of the Aquamarines are a sweet cool Blue. The total Aquamarine and Black Onyx Weight is approximately 470.00Cts- The 25 Faceted Aquamarines are each approximately 18.60Cts each. This will look gorgeous with her blue outfits. Aquamarine is the March birthstone. This 470Ct Aquamarine Necklace will be auctioned to the highest bidder at $1 No Reserve.