Wulfenite from the Czech Republic is not all that common, but this matrix piece is covered in transparent, tan crystals up to .8 cm across. There are also several gemmy, colorless calcite crystals which reach .5 cm across - cerussite! The matrix is comprised of neotocite, which is a rare manganese; iron silicate. A very rare and probably old specimen. I have never seen one before. 7.8 x 4 x 2.3 cm