BUYING POTTERY, like buying anything else, takes a knowledge of the fine points of the craft. The more you know, the happier you'll be when you bring the pot home. Here are some tips by area experts.

Elena Canavier is something of a national patron for the crafts in her role as assistant for the arts to Vice President and Mrs. Mondale. (Before, she was crafts coordinator for the National Ednowment for the Arts.)

A ceramist in her own right (she makes what she calls "interpretive, decorative vessel objects. She considers weight and balance, color and texture, in choosing a mug: "I would hold it to see if it would feel too heavy when full and to see how the handle feels in my hand. I consider the size and how much I want it to hold."

Canavier said "the main virtue of a handmade object is that you can get the craftman to make exactly what you want."

Most of the dinnerware Canavier buys is stoneware, which she mixes and matches. She feels that most of the potters from whom she buys use glazes with enough variation from piece to piece that "even sets don't look monotonous."

Pamela Kirk is a potter and instructor in ceramics at Antioch University's Visual Art Center in Columbia, Md., and, more importantly, an indefatigable collector. What does she buy? "Anything, anything I see that I like." And that ranges from modern sculptural forms to pre-Columbian and old Japanese work.

Walking through a recent show in Antioch's gallery, which she curated, Kirk said, "Look for simplicity in shape as well as decoration. For example, people are often attracted to Chinese blue and white ware. To choose a good pt of this style, look at the quality of the brushwork to be sure it was done by hand rather than stencil. Stenciled designs have exact repetition; real brush work has more freedom and imperfections."

On a molded a piece, Kirk said, check the seams and joints. "A well-made piece won't have obvious seams. Look at the bottom of the pot to see how it is finished. A simple form can contain a more elaborate to see if the design and form work together."

In addition to attending shows and galleries, Kirk finds her pieces at flea markets, antique shops and in nooks and crannies.The problem with this method, she acknowledges, is finding something without knowing what it is or how much it should cost. She researches her finds in books and museums. She has found the Smithsonian's Freer Gallery especially helpful.The Freer's appraisals are by appointment on Tuesdays September through May. The ceramic expert will identify pieces but will not give a monetary value.

Richard Lafean, who chairs Antioch's ceramics department, looked in as Kirk was talking and added, "If a pot is balanced, no matter what "rules" are broken, the piece works." At crafts fairs, he said, "Look at a lot very quickly, and you will surely come back to two or three you really liked." Lafean confided, "If I really, really like one particular aspect of a pot, I'll buy it.

"No matter how much of a novice a would-be buyer is, there has to be some gut feeling about the selection. If you don't let intuition, as well as intelect, share a part in your choice, it's going to be a cold purchase."

Ken Deavers and Ed Nash are both collectors and shopkeepers. Deavers is owner, and Nash, manager, of the America Hand, a shop dealing exclusively in ceramics.

"A pot should feel like it looks," said Nash. "If it looks light, it should be light when you pick it up, but if it looks heavier then that's the way it should feel."

This carries, of course, only up to a certain point: If the pot in question is, say, a large bowl, it should be heavy enough not to feel fragile but light enough to be picked up when full of dough, salad or whatever. Moreover, a good utilitarian pot should have a clean bottom (pots aren't glazed on the bottom because the glaze would stick to the kiln shelves), and the glaze should run down to the foot of the pot.

He ysed the teapot, one of the forms potters find most difficult to makeboth functional and esthetically pleasing, as an example of function: "The potter must leave enough space between the mouth of the pot the handle to get the lid off easily, it must pour without dropping; the spout must be placed high enough to be able to fill the por completely, and the handle must be strong enough for constant use."

A casserole must have good handles on the sides or a widely flared lip so it can be easily picked up with potholders. The lip of the casserole and the edges of the lid should be rounded, rather than thin and pointed, to avoid chipping in use.

Plates, Nash said, should have a glossy or semimatt rather than flat matt glaze, because a true matt glaze will scratch and show knife marks from use. The surface of the plate should not have incised decoration, which would be difficult to clean.

He explained that lead glaze is virtually nonexistent in stoneware and porcelain by today's American potters because lead is not used in pottery fired to such high temperatures. The only pottery likely to be lead glazed is low-fired earthenware from Mexico or other South American countries. Such imports should definitely be analyzed before using to hold food.

"One-of-a-kind work is harder to talk about," he said, "because people's responses are so much more personal. Craftsmanship, however, should still be a consideration - surfaces suitable to shapes, a good relationship between the weight and volum, care and neatness in glaze application, well-attached handles and decorations. A good pot can be ruined by the wrong surface treatment. The reverse is not true; you cannot take a bad pot and make it great or even good by the surface treament. If the copper-red glaze is gorgeous and the bowl is dumpy, it's simply a great glaze on a lousy pot."

On pricing both Deavers and Nash admitted, "That's a hard one." But they offered a few estimates. Coffee mugs in stoneware simply glazed with little or no decoration are likely to run $4.450 to $6.50 each; a decorated or hand-sculptured mug will be $6 to $10. A stoneware teapot would run between $20 and $40 depending on the size; the same in porcelain would be $35 to 60.

Nash advises beginning buyers to start with what is called "production work," many nearly identica items (such as mugs) made on a potter's wheel instead of the more expensive individual pieces.

Deaver, as a final word, warns that you shouldn't expect handwork, even in sets, to be all the same height or size or color or same anything. Uniformity is the province of the machine, not people. It's the veriations that make handmade crafts one-of-a-kind.