Calcite crystals on matte brown matrix Pseudomorph and some pieces have hollow

and some pieces have hollow cores

I suspect the very small botryoidal peach-colored crystal spotting the specimen (the largest is visible just right of center in image 4) may be the world's smallest rhodochrosite

" this type of calcite from the famed Santa Eulalia mining district grows in hedgehog clusters of sharp dogtooth (scalenohedral) crystals

There are black spheres of hematite spotting the point

Place it on a surface that will stay dry to avoid this

Calcite crystals on matte brown matrix Pseudomorph and some pieces have hollowLocale: Santa Eulalia, Chihuahua, Mexico Approx dimensions: 4. 5 x 2. 25 x . 75" Approx weight: 107g This specimen from Santa Eulalia has modified rhombohedral calcite crystals on a brown iron oxide matrix. Ripples and flow patterns indicate water was involved in the deposition of the brown sandy textured layered crust, which appears matte but glitters under direct light. The large calcite crystals are heavily included with hematite (iron oxides) and