Jacques Rouet, the head of Christian Dior, didn't know he was in the house of a jewelry designer when he visited the French embassy recently. Madame de Laboulaye was wearing a pearl choker styled for her by her husband, the ambassador, who conceived a necklace clasp that can be changed to match the color of a dress. For their first formal dinner at the embassy, Madame de Laboulaye was wearing an amethyst clasp, but she has two others.

Among Rouet's projects on this trip was a visit to the hosiery mills in Charlottesville, N.C., part of Dior's $80-million business in the United States.

David Wolfe, Neiman-Marcus vice president, specializes in furs, from picking skins at the auctions in Russia to buying and styling the actual items. Wolfe owns seven fur coats, but really has never been happy with any of them. "Too hippy," he complained and "too skirty." But not so with the Conrad Bell furs recently introduced at that store.

Bell is a $600-a-day New York model who, on a photo assignment in Chile for Neiman-Marcus, sketched to fill in the hours during a long snow storm when pictures couldn't be taken. Wolfe saw the Bell sketches and chose some to make up in coats for the store.

Among the Bell designs are a furlined parka and a coyote coat that comes with a sleeveless slipcover to wear in the rain, which folds up into a pouch.

One-third of the furs sold at Neiman-Marcus locally are for men, according to Wolfe.

On the list of offerings to buyers at the 78th annual fur auction in the Leningrad Fur Palace: red, white and blue fox, seal and squirrel, cat (10,000 skins), 6,000 dog skins.

David Wolfe, who regularly attends the Leningrad auctions, says he never stays around for the auction of cat and dog skins and doesn't know of any American store that would buy them. "I find it too distasteful to even be around when the auction of those skins is going on," says Wolfe, who adds, "It comes to a whole social approach to things and a judgment of what is usable in nature in one country being unacceptable in another."

It is more talk than fact, says Eileen Ford, head of one of the top New York modeling agencies, that designers are scouting out more bosomy, rounder models. "It's what they say when pressed to make news," says Ford, who finds the skinny, tall, flat-chested model still in top demand.

What she has found, too, is that the current crop of models is working longer than a decade ago. She says they are better able to preserve themselves, more aware of a need to exercise.

Ford, who was in town to promote her book, "Beauty Now and Forever, Secrets of Beauty after 35," says sex life has a lot to do with the way one looks. "I do think that if you have an active and happy sex life you look better," she concludes.

Take a second look at the damask tablecloth when you take it out for the holidays. It may be the fabric of your next spring outfit. Several designers, including Calvin Klein and Scott Barrie, are showing cotton damask, indicating a return to sturdier fabrics. Another spring revival - cotton leno, the open weave that adds to the lightweight quality in separates at perry Ellis and Anne Klein.

And now from the man who deserves the credit for initiating wide men's ties, a decree that ties will get narrower and shirt collars shorter. Leading menswear designer Ralph Lauren has started to make shorter collars and narrow neckwear in his more modest-priced Chaps collection, and will show a similar direction in his January Polo designs. Both lines will have ties at 2 3/4 and 3-inch widths, as well as 3 1/4 inch, which he says will be his basic width. (Current best sellers in better ties are four inches or 3 3/4 inches at the widest point.)

Lauren doesn't expect the narrow tie to "overtake the market," he says, but it will cause some excitement and stimulate business, especially now that tie-wearing rules are relaxed and ties show up with things like bomber jackets, not just with formal suits. "It's the start of a gradual change in proportion," says Lauren. "That narrow tie must be worn with a smaller knot and with a smaller collar."

Lauren says the new narrow tie will attract two types of buyers, "the young guy who has never worn narrow ties before and wants a new look, and the conservative man who has always worn them and is excited to finally find them in some new patterns."

Emilio Pucci, Italian fashion designer whose innovative spotswear designs, bright color prints in jersey and ski-wear were an important fashion influence inthe 1950s and 1960s, has been enlisted by Hawaii's department of planning and economic development to help promote Hawaiian fashion week next month.