AS IN Grand Union's special stores, warm tones of wood make Giant's Someplace Special look more inviting than the average supermarket. But if Grand Union goes in for California chic, Someplace Special's byword is European elegance. The sight of long loaves propped on end, pastry chefs trimming tarts and prepared food arranged gracefully among fruit and greenery evoke thoughts of shops in Milan, Paris or Vienna. Only the meat counter disappoints, for it is so high one cannot watch the flash of the butcher's knife, a chief fascination of marketing in Europe.

Rather than using bright stripes and boaters to conjure up a casual, small-town atmosphere, as Grand Union does, Someplace Special dresses its staff in white shirts, dark bow ties and vests to create a feeling of crisp formality. The store holds consistently to this theme, for unlike the other experimental stores, Someplace Special carries only specialty and gourmet food. One finds party paper goods here, but no long, dreary aisles of Pampers See GIANT, L2, Col. 2 SOMEPLACE SPECIAL GIANT, From L1 and paper towels--all of that is across the street in the regular Giant.

A natural first stop is the bread and pastry counter, where the smell of a loaf of San Francisco sourdough french bread is irresistible (it tastes good, too). Onion pumpernickel, challah, rye and bagels are also up for grabs. The rugelah cookies, tasting of raisins and cinnamon, are tiny and delicious, and an entire Amaretto Royale Mousse cake can be taken into possession for a mere $29.95. A more modest purchase might be a dozen chocolate chip cookies, sweetened only moderately so the taste of chocolate predominates.

One expects to pay for the high quality generally found at Someplace Special, but some prices seemed out of line. For example, quail cost $11.99 a pound, compared to $6.49 at the Belleview Grand Union, and out-of-season fresh asparagus, priced at $4.49 a pound, cost $2.39 the same day at Safeway International.

At the cheese counter, one can taste and order portions from wheels of cheshire and jarlsberg, leyden and parmesan, all nested beautifully among pears and bunches of grapes. You need wine to go with the cheese and Someplace Special has it. Alas, the selection seems too limited to attract the serious connoisseur and too expensive for the jug-wine crowd.

The deli presents a persuasive argument for giving up home cooking. Particularly tempting are a pasta roll stuffed with spinach and ricotta, broiled whole baby chickens, smoked fish, pepper brandy pa te', gingered baby carrots, blanquette de veau and caponata. A bowl of applesauce studded with cinnamon sticks adds a homely touch to the elegant spread. Freshly made chicken and veal stock give home cooks a way to save time without sacrificing quality; other kinds of stock and sauces are available with a little prior notice.

The prices of the prepared foods are high, but food coordinator Brody promises that everything is made with the best ingredients. And the food won't have a soggy, over-the-hill quality once you get it home, she says, because it has not been warmed on a steam table or in a microwave. Instead, the kitchen leaves the final cooking for the customer to do at home or prepares dishes hot for pickup at a specified time.

Unusual cuts at the meat counter are venison steak, buffalo rib eye steak and boar ham steak. One might select tiny French lamb rib chops already bathed in a marinade, oxtails to make a hearty soup or beef aged and cut in the store.

Among the exotica in the produce department are shiitaki and oyster mushrooms, fresh figs and water chestnuts. Fresh dill, marjoram, oregano and other herbs, as well as lettuce, come from Giant's own hydroponic gardens. If the idea of spending $7.99 for a head of garlic ("elephant" variety though it is) makes your head swim, check out the admirable green beans, each one the size of a pinky and priced at only 79 cents a pound.

Overwhelmed by the possibilities? Ask the store's "hostess" to help you plan a dinner party, complete with flowers arranged in the store. The kitchen will custom-cook a recipe or allow you to order your groceries by telephone--for a price, of course. You can even order gift-wrapped food.