A self-described recovering cocaine addict testified yesterday that she sold crack to D.C. Mayor Marion Barry on about 25 occasions over a three-month period in 1988, normally providing the mayor "his usual," three $30 bags of crack cocaine.

Lydia Reid Pearson told the jury that she twice brought crack cocaine to Barry at the executive suite of the city's Frank D. Reeves Municipal Center at 14th and U streets NW.

"He would call me, then come by. I would give what he wanted: crack cocaine," Pearson testified.

Pearson is the first witness in the three-week trial other than Barry friends or business associates to testify that she sold drugs to the mayor.

On cross-examination, R. Kenneth Mundy, one of Barry's attorneys, used Pearson to attack FBI informant Hazel Diane "Rasheeda" Moore, who Pearson said told her "she was going to get" the mayor after their romantic relationship ended in 1988. Pearson lives across the street from Moore's mother in Northwest Washington, and she testified that she and Moore were close friends when the two attended Roosevelt High School in the late 1960s. She said she became reacquainted with Moore in 1988.

Mundy, who will continue his cross-examination on Monday, did not challenge Pearson's assertion that she sold drugs to Barry, testimony that supports the prosecution's conspiracy charge and provides the basis for one of the 10 cocaine possession counts against the mayor.

Throughout Pearson's testimony, Barry sat back in his chair at the end of the defense table, looking directly at Pearson without changing his expression. Pearson returned Barry's stare only once, when prosecutor Richard W. Roberts asked her to identify Barry for the record.

At the end of the day, as Pearson left the courtroom, she paused at the door to ask a courtroom artist if she could have a copy of a sketch of her on the stand.

Pearson testified that at first, she sold drugs to Moore that she understood were intended for the mayor. Later, Pearson testified, she sold crack directly to Barry, who stopped purchasing drugs from her only because her telephone was disconnected and he could no longer reach her.

Pearson's name surfaced in the trial last week when prosecutors played a videotape of the undercover sting at the Vista Hotel. In the videotape, Barry remarked to Moore that Pearson and her boyfriend, Ron Manning, had been dependable suppliers.

"That couple still live across the street from you?" Barry asked on the tape. "What was their name? Who, Lydia? . . . What is, what's the guy's name? Ron? Oh yeah, they came through pretty good at times, you know?"

In her testimony, Moore said that she obtained crack from Manning on credit and that Barry ended the arrangement when her tab got too large.

U.S. District Judge Thomas Penfield Jackson stopped Pearson before she could testify about the credit arrangement, ruling that Pearson had no personal knowledge about the agreement.

When Barry called her, Pearson said, he would not mention drugs directly. Pearson quoted Barry as asking: " 'Is anything happening? Is everything all right?' It would mean whether I could provide him with the crack cocaine.

"He would call and let me know . . . . We would make the deal. I would give him the bags, and he would give me the money," Pearson testified. "His usual amount was three $30 bags . . . four-tenths of a gram . . . . Ronald's thirties were big."

Prosecutors granted Pearson immunity from prosecution in exchange for her testimony.

Each time she sold drugs to Barry, Pearson testified, the mayor gave her $100 for the three $30 bags of crack. Often, she said, Barry let her keep the $10 change, which she said she used to buy drugs.

Although Roberts described Pearson in his opening statement June 18 as an addict, Pearson said yesterday that she is a recovering addict.

She said Manning was addicted to heroin and she was addicted to cocaine.

"I used the past tense," she said.

At times, Pearson's voice sounded uneasy and her movements appeared slightly awkward. Mundy did not ask Pearson how long it has been since she used cocaine.

Roberts led Pearson through a description of the three times she said Barry came to her house on Taylor Street NW. Before the first time, Moore asked Pearson for the use of a room, Pearson testified. Moore said that because Barry is married, Moore's mother would not approve of their relationship, Pearson said.

Pearson described each of the three visits the same way. Barry and Moore arrived separately and met in a rear, second-floor bedroom, Pearson said. After about an hour in the room, Barry emerged and left, she said. Afterward, Pearson testified, she went to the room and found Moore -- whom she referred to as Hazel, Moore's real name -- smoking crack. On two occasions, Pearson said, she joined Moore in smoking the drug.

During his first visit, Pearson testified, Barry talked to her about Moore's addiction to cocaine and about the possibility of getting Moore into a treatment program.

"He said it was becoming a bit too frequent, and he could see she was really becoming abusive and he wanted to help her. He did care for her. He had feelings for her," Pearson testified.

Pearson also described her work with Project Me, the city-funded self-improvement program for teenagers conceived by Moore in 1986. Pearson testified that she joined the program in its final days in 1988, after Moore was no longer active in it.

Under questioning by Mundy, Pearson testified that Moore dropped out of the program in 1988 because of her addiction to crack. In her testimony, Moore acknowledged telling a grand jury that she dropped out because of drugs, but she also testified that Barry threatened to cut off funding after she refused to engage in sex with him at a Washington hotel.

Earlier in the day, in his questioning of an FBI agent present at the mayor's arrest Jan. 18, Barry attorney Robert W. Mance sought to raise questions about the FBI's handling of two crucial pieces of evidence -- a crack pipe allegedly used by Barry that evening, and a small rock of crack cocaine found inside his coat pocket.

On Thursday, FBI evidence technician Frances Henning testified that she found the rock of crack when she went through the jacket at FBI headquarters on Jan. 29, 11 days after the Vista sting. Yesterday, Special Agent Frank O. Steele testified that he had been handed the jacket to search just moments after the mayor's arrest, but overlooked the pocket where Henning later found the crack.

Why? Mance wanted to know. Steele replied that he searched the coat hurriedly, looking for the pipe.

"The {FBI} people in the room next door to {Room} 727 were in contact with headquarters by telephone, and they were relaying to me that there was concern that the crack pipe could not be located and that I was to find it as fast as possible," Steele said.

Steele said it took the agents an hour and 20 mintues to find the pipe, which turned up in an eyeglass case in a bureau drawer.

The presentation of technical evidence from the FBI continued later in the morning with testimony from FBI toxicologist Thomas Lynch, who said that he had conducted tests on blood and urine samples taken from Barry the night of his arrest. Both tested positive for recent cocaine use, he said.

Staff writer Tracy Thompson contributed to this report.