Even during a shopping break you can enjoy antiquing. Or at least looking. Here are some restaurants that may tempt the antiquer's eye: CASPIAN TEA ROOM --

4801 Massachusetts Avenue NW. 244-6363. Open daily. AE, MC, V. Reservations suggested. Full bar.

This shopping-center tea room has an embassy-elegant air. The front is clearly commercial, with a pastry case displaying a sumptuous selection of tarts and cakes grandly decorated. But in the back there's a showroom of antiques even more sumptuous -- gilded, inlaid and draped with velvets. In between is a dining area reflected in gilt pier mirrors and lined with flowered-rose wallpaper. The service is less polished than the furniture, with sometimes-long waits for food and occasional confusion over who gets what. But the food is often worth the wait. The menu is largely Persian dishes with pan-European accents. Desserts are excellently French; European dishes range from dull to fine; and the Iranian dishes are invariably delicious. The kebabs are likely to be oustanding, and there's fessenjan, the chicken-pomegranate dish that is one of the great legacies of the Persian empire. At dinner, fish oferings are good choices among the Western dishes. And eggs have been very well handled, from just-runny Eggs Benedict to a nicely done, softly layered omelet. But at the Caspian Tea Room the rice is the star, accompanied by butter to moisten it, tiny bowls of tangy, spicy ground sumac to sprinkle over it and a tiny cup with a raw egg yolk to work into the mixture while the rice is steamy enough to cook it to a custardy texture. Save room for beautiful pastries -- strawberry napoleons with fine flaky puff pastry, butter cream tarts with the taste of butter, creamy mousses in thin chocolate shells and Bavarian creams glazed with tart apricot. A little heaviness here and there doesn't interfere much with their dazzle. FALLS LANDING --

774 Walker Road, Great Falls. 759-4650. L daily except Saturday, Sunday, D daily. Closed Monday. AE, CB, DC, MC, V. Reservations required. Full bar.

The happiest of marriages is that of a seafood restaurant with a seafood shop. Falls Landing is run by Cannon's, whose branch store is just a few clapboard houses away in a pretty little "village" of shops. The professionalism shows in the food-buying. Oysters on the half shell one day proved the best I've had in town -- large, fat and briny. The fish is obviously fresh and of high quality, the crabmeat in large, snowy lumps and the shrimp big and clean-flavored. Swordfish brochettes are large chunks of full-flavored fish crusty with grill marks and meltingly tender, interspersed with big crisp shrimp. It's one of the area's most delicious seafood dishes. The crabcakes, too, are impeccable. Otherwise, Falls Landing too often falls short of the superlatives its fresh fish imply; a flounder was a mite overcooked, a salmon steak just the wrong side of dry. The fried seafoods I encountered were made with all the right moves; still they were dry and boring. If main dishes dip below expectations just after a broiled fish or raw oysters have led you to expect great things, it's a shallow dip. The food is good, by and large, and worth every one of the roller-coaster dips on the road from the Beltway. PORTNER'S --

109 South St. Asaph Street, Alexandria. 683-1776. L daily, D daily except Sun. Sunday brunch. AE, MC, V. Reservations suggested. Full bar.

Here's what you'll love the first time around at Portner's: The restaurant glorifies appetizers. The deep-fried potato skins are five crispy cups filled with melted cheddar, sour cream and scallions or sour cream and huge dollops of black lumpfish caviar. Steamed clams -- or clams and mussels -- are also substantial and delicious, their broth a light cream perfumed with shallots and herbs. Portner's Brunswick stew -- available as an appetizer or main dish -- tastes bright and fresh, with big pieces of boneless chicken, chunks of tomato, corn and lima beans in a light-textured broth. Very good, though excessively sweet. And therein lies an all-American flaw of Portner's. Too much, too sweet. Among main dishes, the best I tried was crabcakes -- beautiful golden ones that had been pan-fried rather than deep-fried, made with lump crabmeat. Good food, but not necessarily good value. Portner's slips with its tough and tasteless hamburgers, a major focus of the menu. A bad investment. Then there are the middling dishes: the steak that looks beautiful but lacks crustiness; the duck salad that consists of decent-enough greens but is topped with mushy and tasteless duck. Dessert gets a spotlight at Portner's. The hot fudge cake is called the Ultimate, given the price and the size. It is indeed good, but should be reserved for a separate visit. The trip to the upstairs dining room, via a grand carpeted staircase bordered by a magnificent banister and past stained-glass skylights and antique furniture, activates one's anticipation of a grand meal. In the end though, Portner's is a sumptuous pub, and its food -- at sumptuous prices -- is pub food.

1789 -- 1226 36th Street NW. 965-1789.D daily. Closed Sunday. AE, CB, DC, MC, V. Reservations suggested. Full bar.

1789 is a serene 18th-century house serving imaginative French food. The dining rooms are charming, with fireplaces, and the main dishes range from rabbit to reindeer. But most interesting are the daily specials: oysters in puff pastry or in garlic-parsley butter; salmon sauced with two caviars or stuffed with spinach; pheasant or lamb or sweetbreads in orange sauce. Sauces are delicate, vegetables beautifully cooked and sensitively seasoned. Chicken breast with pecans and morels was not a knockout, but it was well prepared. Grilled lobster was slightly undercooked but was as fresh as one could hope for and accompanied by a dill-caviar sauce that suited it well. One could wish for a more informative or evenly modestly priced wine list, but the choices are intriguing. And for dessert, 1789 serves such extravaganzas as Gateau St. Honore under a cloud of spun sugar.