"Gold come in many colors," says Louis L'Amour. "Some of it has so much silver mixed in that it is almost white -- you get that out around Colorado -- and then there's some that's almost red."

For the world's most successful writer of Westerns, the color of gold is black-and-white, and it is found in the pages of novels, which he produces at an average rate of three a year -- still not fast enough for L'Amour fans, who have already bought 110 million copies of his 81 books.

Gold is the theme of his latest novel, "Comstock Lode," and it runs through his conversation these days the way it used to run through the ground in some Western states.

L'Amour, who refuses to reveal his age, looks and acts like the kind of people he writes about. A big, chunky man with a broad, open face and the slow speach of the American West, he could be a real-life Ben Cartwright -- or a miner, lumberjack, prizefighter, merchant seaman, longshoreman or army officer. Before he started writing in the late '30s, he was of the above, and much of his experience has been useful as background for his books. Like mining gold:

"On the Colorado and San Juan rivers, it doesn't pay to pan it out -- it comes so fine you just loose it that way . . . I've washed diamonds out of the sand in South Africa -- came out with a sack of 40 pounds of diamonds and thought I was going to be a rich man. Turned out only two of them were worth marketing."

So he had to find another way to get rich -- and he did.

He became one of the best-selling authors in history. In addition to "Comstock Lode" (already on the best-seller lists), his other books -- most of them published by Bantam -- include one collection of poetry that you can't find anywhere, a few shortstory collections, and the novels. They are usually set west of the Mississippi in the years from 1860 to 1885, though some go back to England of Elizabethan times. All of his novels are still in print, though some are easier to find than others -- because the name Louis L'Amour is usually right at the top, in letters larger than the title.

On a recent visit to Washington, L'Amour held a traditional autographing session (at the Pentagon bookstore, where he is very big), signing more than 300 books in an hour. But his main purpose was to talk to the employes at District News, the massive distribution agency that stocks nearly every paperback rack in the Washington area. The man who decides where a book is placed in those racks has a serious effect on sales; a book at eye level will sell better than a book down near the floor. Consequently, many authors want to talk to District News, said Rich Porter, director of marketing. "Most of the time we say no. In the case of Louis L'Amour, we were happy to say yes."

L'Amour spun stories of settlers and Indians, delved into the fact and folklore of the six-shooter, discussed how he gets ideas -- and gave the employes a pep talk: "I know the importance of positioning and exposure," he said, "and I really appreciate all you're doing. I write the books, but you follow through. You put them out there and you deliver the goods, and I really am grateful."

He also answered the question that Porter said is uppermost in the minds of the people delivering paperbacks to the market: "They touch the book and they look at it and they wonder, who is this guy? Where does he get his ideas?"

"I do research all the time, and I get all of my ideas from factual material," L'Amour said. "The period I write about is the best-documented in human history. There are plenty of newspapers, diaries and army reports. I remember once, hiking in the mountains, I found a cabin with old newspapers pasted to the walls for insulation. I spent several days there, taking those papers off the walls, layer by layer.

"I see a situation in my research, think 'That would make a good story,' invent a couple of fictional characters and put them in that situation. I can move tham around the way I want to and still keep a lot of historic reality."

Research helps to explain why L'Amour's novel have a verisimilitude rare in Western fiction. It is not the product of schooling: He is self-educated, having left his North Dakota home at 15 to seek his fortune traveling around the world. Family history is also a significant ingredient -- his Irish-French ancestors were part of the Wild West era.

"My grandfather fought Indians," he said. "He was killed and scalped by Indians. When they weren't fighting, some of the old Indians would come around and see him. They were enemies, but when they aren't at war fighting men tend to like and respect one another.

"I've personally known about 30 of the old gunfighters and outlaws -- Emmett Dalton, for example, who was the last of the gang, the only one who survived their last raid. When I knew him, he was selling real estate in Los Angeles, and he hadn't changed much. He was still a bandit, but he had a different modus operandi. I was lucky in my timing -- if I had come along 10 years later, it would all have been gone."

L'Amour did not originally set out to become a writer of Westerns. "For as far back as I can remember," he said, "I have always wanted to tell stories. But when I began to be a writer, I intended to write about the Far East.I had spent some time in China and India, and they fascinated me. I had only written a few Western stories before World War II, but when I got out of the army I went up to New York and ran into an editor who needed Western stories -- 'Write me some stories,' he said, 'I need them right away.' Then an editor from Fawcett saw one of the stories and told me, 'There's a novel in this -- write it.' I wrote it, and John Wayne bought it and turned it into 'Hondo,' and I was started. You might say that becoming a writer was something that just kind of happened."

But producing books at the rate of three or four a year does not just happen. "I work a lot," he said. "I get up early and think for a while before I start writing, but I'm usually at work by 7:30 in winter and an hour earlier in summer. I write until noon, then have lunch and work a while longer. In the afternoon, I work out on lifting weights or punching an exercising bag. I do a lot of hiking in the mountains -- Colorado, Wyoming and Utah -- and you have to stay in reasonably good shape to do that."

He lives outside Los Angeles with Kathy, his wife of 25 years, and his two children -- a 19-year-old son who wants to be a movie director, and a daughter, 17, who is planning to become a singer or actress. In the room where he works, there are two electric typewriters, and there is usually a book in progress in each of them. "It's not true that I type on both typewriters simultaneously," said L'Amour, who is sensitive to the criticism that the writes too fast. "I have to move from one typewriter to another, and sometimes I leave one of them untouched for days or weeks while I work on the other one. Right now, I have a story in one typewriter and a nonfiction book in the other."

L'Amour used the word "nonsense" a lot when talking about the mystique of writing. "People think that if you produce a lot it's not good -- nonsense. Look at some of the old composers -- Bach with his hundreds of cantatas, Haydn with 104 symphonies -- dozens of them are masterpieces. And I think it's a lot harder to write a symphony than a book. People ask me if I have to be in the mood to write, and that's nonsense, too. A job is a job. I learned a lot about how to write while I was working at the business end of a shovel."

L'Amour's own collection of books is largely hardcover -- vintage works from the period he writes about, including many that are irreplaceable. He doesn't mind letting people use them, but the books stay there.

"Steve McQueen used to come to my library a lot and read," he said. "I don't lend books to anybody -- that's the best way to lose a library, and I got too many books that way myself. I have loaned only one book in the last 20 years, to the most reliable man I knew -- George Cukor -- and it disappeared. He took it home and either Ethel Barrymore or Katharine Hepburn took it away and left it in a beauty parlor and it vanished. I have never been able to find out who lost it or to get another copy."