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An ordinary woodturning lathe can be used to cut and polish alabaster until it glows with translucent colors. The author's red and pinkplatter in the back is 15 in. in diameter, the largest vase in the center is 10 in. tall and the small pink vase is 2 in. in diameter.Turning rocks is tricky, but that just adds to the fun. And delicatelycolored stones like alabaster, when turned, develop apleasant translucent glow. I conduct turning workshopsacross the country and have been impressed at the popularity oalabaster work. I suppose that's not too surprising consideringturners are such an adventurous lot, eager to chuck on anythingfrom a worm-eaten tree trunk to a variety of fruits and vegetables.In addition, you don't need any special equipment for alabaster,nor any special techniques. The process is just like scraping out awood bowl, only slower, although alabaster does have a couple ofpersonality quirks. It's not so much that the material is contrary asthat it is different and takes a little getting used to.Alabaster is a crystalline form of gypsum (calcium sulfate), which isthe main ingredient in Sheetrock. Gypsum rates a #2 on one commonlyused hardness scale (talc being #1 and diamond #10). Youmight notice some variation in hardness from piece to piece, buteven though it's rock, all alabaster is soft. Impurities are responsiblefor its subtle colors, which can range from translucent whitesthrough pinks, to browns, grays and greens. The turned pieces are abit like crystal wine glasses-lovely, but if you drop one, that's that.You can rough out the alabaster blanks with any variable-speedreCiprocating saw and a large-tootl1 or bimetal blade. A bandsawrunning bimetal skip-tooth blades at slow speeds will cut alabaster.The low-tech chisel-and-mallet approach also works fine. Currently,I'm mounting the rock on the lathe and using an air chisel toknock off enough material to balance the piece, then using a narrowscraper known as a Stewart Slicer (available from DennisStewart, 2502 N.W 4th Ave., Hillsboro, Oreg. 97124; 503-640-3089).For the actual turning, I use carbide-tipped scrapers. Commerciallyavailable woodturning tools are fine, but I made my scrapers by unbraZingcarbide tips from old router bits, then rebrazing them ontosquare-stock steel (available from KBC Tools, 6300 18-Mile Road,Sterling Heights, Mich. 48078; 800-521-1740, or 800-482-1047 inMichigan). You can also order tools specially made for alabaster fromJerry Glaser, 8341 Delgamy Ave., Playa del Rey, Calif. 90293. I sharpenmy carbide tips with a 120-grit silicon carbide (greenstone) wheel.High-speed steel scrapers are best for the finishing cuts (see top,right photo on the next page). The steel edges aren't as durable ascarbide, but they produce a cleaner cut, probably because tl1ey canbe sharpened to a finer edge. I grind tl1e ends square with nobevel. This way I can use one side until it is dull, then flip it overand use the other side. These high-speed steel scrapers are availablefrom Craft Supplies USA, 1287 E. 1120 S., Provo, Utah 84601;(801) 373-0917. Craft Supplies also sells double-faced tape, thetype of pin chuck I use (the version included with combination orsix-in-one chucks) and Hot Stuff cyanoacrylate glue, which is invaluablefor holding the work together.Alabaster can be crumbly because of fractures and stresses withinthe stone, so it can break easily on the lathe. I turn each bowl asthin as I dare, usually about Vs in. to 0/16 in. My current successrate is about 80% and would be even lower if it were not for thecyanoacrylate glue. Once the outside is roughed to shape, use thin"original" Hot Stuff on anything that even looks like a fracture inthe stone. If the glue soaks into the crack, I go over it with thethicker "Super T" Hot Stuff and then spray on the Hot Stuff accelerator,which speeds glue hardening. If the glue doesn't seem toflow into the crack at all, I assume the crack just looks like a fracture.I repeat this procedure whenever I get nervous about tl1ingsbreaking, usually on the inside when the piece is about 1/4 in. thickand always just before the final thickness.Safety hazards-Be aware: There is always a chance the block willshatter. Even if everything is going well, dust is a problem. Alabasterdust is similar to Sheetrock dust, so wear a dust mask or a respirator,January/February 1989 55