This is a bright, bubbly plate of gorgeous and translucent Smithsonite, which seems to be overlaying a darker layer of Smithsonite (possibly included with blue aurichalcite) , and the contrast gives the piece a depth of color that is unusually rich and vibrant. It is a three-dimensional "plate" that is not quite flat, of curving bubbles of Smithsonite to about an inch, grown over each other and over the brecciated matrix beneath. Very minor edge bruising but only at the periphery. From the noted collection of Marty Zinn, who himself lived in New Mexico and built a specialized suite of NM minerals over many years