"WHY NOT TRY INTARSIAS"

An original Indian portrait by Al and Myrl Cook, again shows imaginative use of material, perfectly fit individual pieces, and true understanding of portrait art.

   Now you are ready to cut your pattern parts. The Cooks use a special trim saw with a 6 inch blade only 25 thousandths in thickness. They say it is accurate for cutting smoothly and close to the exact line. (I had such a saw years ago, but my husband complained I was too hard on the blades. These have since been improved.) Cooks blade is a sintered Norton. They also have a ten inch trimsaw.
   Lapidaries will guess the next step, which is to wash each oily piece of newly cut stones in warm water and detergent. Grinding is the next process. Al and Myrl recommend a 1 ½" x 8" wheel of 220 grit. Keep it wet and keep it true. The edges of the wheel should be kept sharp. Use a tool rest to lay your slab on when grinding. Hold it at a perfect right angle to the wheel with the rest as close as possible to the surface of the wheel. Grind down accurately to each part of your line.
   After a piece is ground you are ready to cement it to the correct and exact position on the plywood backing. For this epoxy is most satisfactory. Use sufficient adhesive so that it will ooze out from all the edges and push up to fill the joints, leaving a slight epoxy bead on the surface where pieces meet. Don't worry about this beading as it will be removed in the lapping operation. Put a 100-watt light bulb in a flexible necked lamp and position the bulb over the newly cemented are for a period of at least 30 minutes, but not much longer. The heat from the bulb, if it is within an inch of the surface of the slab, will cure the epoxy sufficiently that the slab will not move when you put the next one in place. Before placing the next piece, see that background and exposed edges are clean. The cement from the next piece will form the beading where the two edges are joined, and extra cement on both of the edges to be joined would be too much.
   As you work you may need to do some minor regrinding in spots, as each piece must fit the next one just exactly in every direction and must cover the designated section of the board. Mr. Cook says to cement in several pieces, but leave several open sections around them to be certain of the tightest final fit. When all the pieces are in place there should be no unevenness and no cracks between the pieces.
   The grinding (lapping) is next. Cooks lap their work face up with an overhead lap on a moveable elbow which Al rigged up. They start the process of grinding and smoothing the surface with 120 grit silicon carbide with a small amount of water. Not too much, as you don't want to wash the grits of the stone top. Every 10 or 15 minutes use a damp sponge and wipe off worn out grits. When the grits are not cutting anymore, you will not hear a sound of friction. After being satisfied that the surface is as flat and smooth as you can get it, wash the intarsia and the lap thoroughly.
   Repeat the grinding process with 220, 400, and 600 grit silicon carbide. Cooks find that for an 11 inch by 14 inch intarsia, the average grinding time will be 3 hours for all the grits, except the first which may take quite a little longer.
   The 600 grit will begin to bring a smooth shine to your work. Check to see that there are no more scratches. If you have guarded scrupulously against contamination of grits your surface should be flawless at this time. Then you are ready for polish. Several polishing compounds are satisfactory, and your choice depends partially on personal preference, and partly on the type of gem material predominant in your picture. If your material is all near 7 in hardness try cerium oxide mixed with a little Linde A with a felt buff and sufficient water for a creamy consistency. The buffing will take you about 3½ hours on an 11" by 14" piece. When the buffing is completed the entire surface should have a uniform mirror-like polish.
   Some people like to frame their intarsias. Others make a stone border around the edge of the picture as part of the intarsia. If you find a frame desirable, it should be simple and fairly heavy, and custom made for your individual picture. The color should either blend or contrast, but should not be bright enough or bold enough to detract from the intarsia.

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An original western scene by the Cooks uses various agates and jaspers to depict topographical features. Notice the clever use of brecciated jasper for the leafy tree bough, and the petrified wood fence with the highlights and knots placed just right.

Cooks' intarsia jewelry is unique. These pieces are backed with silver and are only 1/16 of an inch thick. All pieces are usable as bolas or pins.

   Besides the petrified wood tabletop, the scene and Indian portraits the cooks make clever intarsia "cabochons" for jewelry. These carefully made miniature masterpieces are cemented to sterling silver background. For jewelry intarsias, cut the slabs only 1/16 inch thick, in order to keep the finished jewelry from being too heavy. The silver need not be heavy either, as the stone cemented to the silver will make the entire piece rigid. The pin back or bola slide should be soldered to the silver backing before cementing each piece of stone to the silver, just as you did to the plywood, in the larger piece. Other processes are the same, except that you will also have to finish the edges of the jewelry shapes.
   Nature forms which are distinct and call for sharp outlines, readily distinguishable, plus vivid colors, are most adaptable to the jewelry sized intarsias. These can be plants, animals, birds, fish, individual flowers, fruits, or anything you like and have the proper material for. Or you could use geometric patterns, designs based on archeology or astronomy, or simple figures such as ballerinas, clowns, or masks.
   The selection of material is of primary importance in a successful intarsia, and the cleverest use of material in the Cooks' Indian Chief illustrated this point. The "soft" feathers at the base of the eagle feathers are made form exactly oriented carefully selected pieces of plume agate. Each precisely shaped feather of solid agate looks soft and fluffy and ready to blow in the slightest breeze, exactly like the feathers used in a genuine Indian warbonnet.
   With all the many types of richly colored jasper in the Northwest, Cooks had an excellent selection of material for the hands and face. For each feature had to be subtly blended colors available both lighter and darker than the basic hue to give highlights and shadows so necessary for realistic portraits.
   Other stones used in the headdress are marble, rhyolite, petrified palm fibers and turquoise. The shirt is of yellow jasper, with marble and petrified myrtlewood. Beadwork is indicated by red palm, blue quartz and white marble and agate. Made of traditional catlinite, the peace pipe which the Chief is holding is a light with a piece of fire opal. The background is marble in neutral and pastel tones.
   Cooks have professional gallery type lights above each of their intarsias. Their work was featured at Portland, Oregon at a Northwest Federation Show as well as at the National show in Seattle. They have several projects in mind and new ideas they wish to work out. Working together to create gemstone masterpieces is something they both enjoy. Al and Myrl are modest about their successes, and strike me as typical all-round gem hobbyists, the kind of people who have made this hobby so successful in America. In mastering the art of intarsia they have given other hobbyists new goals, fine standards of workmanship, and have advanced a craft which may prove to be American lapidaries' most unique art form.

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