* Gerald Castellucci remembers that his hand was shaking. The architects for the new AT&T building wanted to buy as much pink granite as Castellucci & Sons Inc., in Providence, had taken out of its Connecticut quarry in a decade -- and all for one building. "I thought, 'God, if we fail, it's unbelievable," he recalls of the meeting that sealed nine months of discussions. Castellucci went to work. He quickly expanded his work force at the Stony Creek Granite quarry from 4 to 15, then lured several master stonemasons out of retirement to train recruits in the art of shaping granite into arches, corners, and mullions. He invested $1 million in new equipment -- more than the previous year's sales.And he kept his crews working overtime for three years cutting 60,000 pieces of granite, some weighing as much as 7,000 pounds. When the work finally started to subside, the prestige of the AT&T contract helped bring in dozens more. "It was the rebirth of our company," says Castellucci.

* Most $56-million companies would get excited if they were courted by a suitor as rich as AT&T. Not Industrial Acoustics Co., in New York City. It coolly informed AT&T that it didn't do ceilings -- not even 325,000 square feet of them. Later, though, the job piqued president Martin Hirschorn's interest when he learned that much larger firms had failed to pass muster with the architect. The ceilings would require custom design, and Hirschorn had built his company's reputation by solving tough acoustical problems. This would be one of his biggest tests. After five false starts and an investment of $100,000, his engineers devised a 75-pound, perforated, vinyl-coated steel ceiling panel that met AT&T's demands for aesthetics, flexibility, and sound absorption. The contract brought the company more than $7 million in sales. And no longer does Hirschorn tell callers his business will "do everything in noise control except ceilings." Enough customers liked the new design for Industrial Acoustics to add a ceiling division, with 25 employees and first-year sales of $4 million.

* AT&T spent $5.5 million for teak paneling, doors, and trim in the building. That was about 4,000 times the amount that Steven P. Jobs and Stephen G. Wozniak needed to start Apple Computer Inc. and the personal-computer industry.

* Talk about labor problems. Building a New York City skyscraper is a task akin to fielding a major-league baseball team whose players refuse to pinch-hit, play more than one position, or change places in the batting order. AT&T had more than its share of such problems in erecting its 647-foot, 1,284-office, 37-story granite tower on Madison Avenue, in part, insiders say, because the managers had troubles of their own. First one, then two, and finally three full-time construction managers struggled to coordinate the work of around three dozen powerful prime contractors and 150 subcontractors and suppliers, most of which were small companies. The contract stipulated that workers from four separate unions had to be brought in just to move the granite from the trucks to the mountings on the building's steel frame. Different masons, with different pay scales, had to be hired to lay stone inside and out. By the time all these tasks were sorted out and completed, the building was almost three years behind schedule and nearly $100 million above projected costs.

* Theodor Sauer comes from the old school. His grandfather began crafting wood in Manhattan in 1886, and the craft has been in his family ever since. Now, laments Sauer, "the quality of things keeps going down." Not everything. Craftspeople at his company, Walter P. Sauer & Sons Inc., labored for four months to cut, plane, shape, join, and polish the 800 pieces of wood in the 32-foot oval mahogany table around which the power brokers of AT&T sit. Some of those pieces are no longer and thicker than a fashion model's well-lacquered fingernail. AT&T paid $37,000 for the table, which, at the instructions of chairman Charles L. Brown, is slightly asymmetrical at its ends to ensure him ample room. Sauer never publicized the AT&T work. But his company has moved on to bigger things: it recently finished a conference table for Equitable Life Insurance Co. that, says Sauer, "was twice as difficult to do and twice as expensive."

* The elevator panels are Turkish onyx, the executive file cabinets Burmese teak. The banners in the employee dining room are Chinese silk, the walls of the executive dining room Italian leather panels. The executive staircases are polished Italian marble. The stonework cost AT&T over $25 million -- 69% more than the average sales of an INC. 500 company.

* Two executives from L. Vaughn Co. flew to West Germany to find the rare, honey-colored Burmese teak specified for the raised panels on 350 doors. The company hired 75 workers just for the AT&T project, increasing its staff by 50%.

* Not all small businesses found it lucrative to work on the AT&T building. In 1979, Chicago Extruded Metals Co. signed a contract for about $200,000 to produce more than 1,000 pieces of architectural bronze used in the 70-foot-high main entrance and in other decorative work. By the time the last piece was shipped, however, company officials were staring at red ink. A producer of brass bar and wire products for industry, the company had decided to attempt the finer work demanded by AT&T's architects in the hope of capitalizing on a growing interest in traditional building materials. But the task of shaping molten brass proved so formidable that more pieces ended up in the discard bin than on the trucks. "It was a very difficult project," laments Davis Anderson, a vice-president. "We certainly did not do as well as we'd have liked." The company has given up on the new market and has returned to what it knows best.

* AT&T spent $200 million for its corporate headquarters, or about $200 per square foot -- twice the going rate for premium office space in major U.S. cities.

* During his eight years as vice-president of C. Roussel Inc., John Pollis had cast bronze sculptures for Nelson Rockefeller and supervised the task of removing the cement insides of Henry Moore's Reclining Figure at Lincoln Center for the Performing Arts. But never had art restoration been so terrifying. For two days, Pollis clung to a 40-foot-high scaffold, 450 feet above the street. He was searching for a way to dismantle the 24-foot-tall, 10-ton winged figure that had stood atop AT&T's old head-quarters for 64 years. As he chipped away at the corrosion under the gold leaf, he forced himself not to look down. Finally, the outline of a metal plate emerged in the head. After he loosened the bolts, workers used 16 tons of rigging equipment to lower the head, neck, torso, wings, arms, and legs to the street. Today Golden Boy -- stripped clean, bathed in anticorrosive chemicals, and recloaked in 12,500 pieces of paper-thin gold leaf -- graces the lobby of AT&T's new head-quarters. C. Roussel charged roughly $100,000 for its part in the statute's face-lift, about a tenth of the company's yearly sales. It would take more than that, says Pollis, who is in his sixties, for him to climb the scaffold again.