Sherman Earrings and Necklace (?)

The colour of this set didn't turn out right. In real life it looks less bluish green.
I bought the set together. The earrings are marked "Sherman" but the necklace is not marked at all. Based on the rhinestones used for both the earrings and the necklace, as well as the construction and the material of the setting, I believe that the necklace is an unsigned Sherman piece. I checked in my Sherman Jewellery - The Masterpiece Collecting book but I couldn't find the earrings nor the necklace.

Any thoughts?

Thanks for looking:)