The barite group of sulfates includes barite, celestite, and anglesite. Barite is used in paints and papers. It is also added to drilling mud in oil wells to control the specific gravity of the mud. Celestite is found throughout the world, mostly in sedimentary rocks. It is named for its distinct pale blue color. The nicest blues seem to be from Madagascar. Anglesite is usually an alteration product of galena. It is usually mixed with cerussite, a carbonate. It is usually colorless, white or gray but can be yellow, blue or green.

I painted a dinosaur on sandstone today.  An albertosaurus. It was a tyrannosaurid, but smaller than rex. And I am not the worlds best artist.

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