I. Fill in the blank 1. A fast sander of slabs is called _____. 2 ._____ machines serve several lapidary purposes: cutting, grinding, sanding, and polishing. 3. Polishing compounds are available as powders, _____ and _____. 4. A cabochon can be dopped with _____ or _____. 5. Using pliers to prepare a preform is called _____. 6. The idea that the surface of gemstones actually flows during polishing was proposed by Sir George _____ and the final glassy layer named for him. 7. A red polish compound is called _____, and a green one is called _____. 8. Gemstones that show more than one color are called _____. 9. The two basic types of facet cuts are _____ and _____. 10. A device for holding tools on a fixed shaft carving machine is called a _____ chuck.

II. Match the letter in the second column with the number in the first __ 1. Diamond wire saw __ 2. Polypads __ 3. Hishi drill __ 4. High speed wide belt sander __ 5. Jam-peg __ 6. Silicates __ 7. Slab grabber __ 8. Sintered diamond __ 9. Pavilion __ 10. Orientation a. Bull wheel b. Early faceting technique c. Holds difficult stones for saws d. Charged faceting laps e. Used for intarsia shapes f. Makes core and hole at once g. Fused, soldered diamond rim h. Bottom part of faceted stone blade i. Determining direction of cut j. Common gem materials

III. True or False? (T/F) __ 1. Immersion liquids are used for studying inclusions before faceting. __ 2. Refractive index and dispersion are of prime importance for faceted stones. __ 3. 14,000 grit diamond is equal to 1/2 micron. __ 4. Silicon carbide is the same as corundum. __ 5. Cast iron pipe fittings are used in sphere machines. __ 6. Anti-freeze is a highly recommended lapidary coolant. __ 7. Numerous short parallel cuts are an aid to blocking out a carving. __ 8. If a scratch develops during polishing, it is necessary to go back to the fine grit. __ 9. Soft gem materials for faceting can be polished with wax laps. __ 10. For chatoyant gems, slab the rough parallel to the fibers. IV. Select the correct word or phrase 1. Some hard gem materials get a better polish with a wooden spool polisher a stainless steel lap a muslin buff 2. The easiest way to get a special shaped cab, such as a heart, correct is to measure both sides of the slab with a calipers use a double template cut the top first and then line up the bottom 3. A difficult material to cut is carnelian kunzite garnet 4. An attachment for making star stones is the “hi-crown” star preformer star cup 5. If the saw starts glazing, a good remedy is to increase the speed touch the edge to a brick add detergent to the coolant 6. Dop sticks can be safely eliminated by using the fingers a wire basket a gripping tool called a cab-master 7. A polishing buff works best when it is saturated with slurry it is almost dry detergent is added to the slurry 8. A highly transparent agate may be tested for iris by cutting a thin slab, oiling it and holding it in front of a light “candling” it in a dark room putting a slab between two lights 9. 14,000 diamond is used for grinding sanding polishing 10. The best speeds for sawing are about 2,000 surface feet per minute 2,500 to 3,500 per minute 4,000 feet per minute Get your answers

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