From the photo you sent, I don’t think it is Hopi, although it is the shape of many Hopi rings I have seen. You can read about the characteristics of Hopi and Navajo overlay here.
From the photo of the back, I do not see the hallmark. I do have record of a YZ and a Y&R hallmark but no YZR. If you can send a better photo, I will dig deeper.
As far as the plant, it is probably a stylized corn plant.
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