DIAMONDS aren't the only gems that last forever. Roger Moore still sparkles as 007 the seventh time around. At 57, he remains durable and debonair, in his latest mission for Her Majesty's Secret Service -- the amusing if sluggish "A View to a Kill."

Moore's 007 is wiser but no less daring as he dangles from dirigibles or snatches costar Tanya Roberts from flaming elevators and flooded mine shafts. The former "Charlie's Angel" plays a squealing but appealing American geologist with a link to this venture's villain, the mysterious industrialist Max Zorin.

Christopher Walken is fun as the vaguely dazed Zorin, a psychotic super businessman with plans to shake up the microchip industry by flooding the San Andreas Fault. Grace Jones is formidable as his feral enforcer, May Day, an ebony Amazon in the cruel tradition of Pussy Galore.

John Glen, who also directed Moore in "Octopussy" and "For Your Eyes Only," sticks to the formula first tried in 1962. Chase scenes, Bond girls and technological gimmickry are mainstays along with the secret agent's talent for deadpan innuendo and wry asides. "I'm an earlier riser myself," declares Bond typically to a new acquaintance named Jenny Flex.

If you like the formula, you'll like "A View," though it's beginning to seem a little worn. Still the film does open with an exciting glacial chase in which Bond eludes a KGB ski team on a surf board. He narrowly escapes in an iceberg submarine driven by a beautiful Bond girl, Mary Stavin. And then, well, you know.

Stavin and the other starlets are as beautiful as ever, but it does take a lot of imagination to imagine them swooning over the mature Mr. Bond in sub or hot tub. Gratitude and father fixations are possible motivations. But such compliant females exist only in the imagination anyway, so what does age (within reason) really matter? In fact, Moore's age seems to give his character more grace and the story more civility, somewhat like Agatha Christie's Hercule Poirot.

Some of the film's most delightful moments, in fact, derive from the interchanges between Moore and his ersatz chauffeur Tibbet, played by the once-dapper "Avenger," Patrick McNee. Other espionage vets on hand include Lois Maxwell as Miss Moneypenny and Desmond Llewelyn in his 12th appearance as Q.

If we are to keep our heroes, our James Bonds and our Captain Kirks, then we are going to have to set aside our prejudices. They're not getting older, just more like Joan Collins.

A VIEW TO A KILL (PG) -- At area theaters.