Dee & I think that all but the left most piece are probably turquoise. Over the years we sold Native American and SW jewelery we've seen all those colors and types of matrix. The left most piece might be glass (Czech) simulated turquoise or one of the various other similar colored stones suggested. It could be turquoise but definitive answers are hard from pictures like these. Handling the piece, backlighting the stones, using a loupe, etc can only be done in person.

We agree that the piece appears to be assembled from non related components.

The stones we think are turquoise are typical of US mined turquoise from the 50's to current times. With wear and absorption of oils many untreated turquoise will "green up" to give similar colors.

It's an interesting piece, to be sure.