HISTORY, Context and Materials" is a sleepy title for a show of 40 enchanting objects, most of them masterpieces in their own way, at the Museum of African Art. This is the last show from the museum's own collection before it moves to new quarters on the Mall next year.

These aren't the sorts of works to remain on shelves for long. More than objects, they have been used -- they have lives of their own, most of them, imparted by the artist or by the people who worshipfully stroked them in shrines, burnishing wood surfaces to a fine sheen.

Such an object is a wooden figure from the Kongo region, a woman who holds a boy child in her lap. Regally, she bears the marks of high rank -- hat, anklets, necklace, certain scarification -- and has mirrors for eyes. You see her almost head-on; that little twist of the backbone is the genius of the artist, giving her presence. Believed to be from the 19th century, she is a fertility figure worn smooth at a time when slavery raids decreased the local population.

"People always ask how old a thing is," says Bryna Freyer, an assistant curator at the museum. "And because most areas didn't have a written system and books, people don't study the great African kings in school. So they don't have a feeling that things went on in Africa for a long time before Stanley and Livingston."

This exhibit explores the what and why of African art as well as the when. The brass staff-of-office belonging to an elder, the ivory figure carved for the top of a fly-whisk, the reliquary object placed on an ancestor's grave -- they are all ornaments with a purpose.

Then, just when you think you have the context right, says Freyer, you find a small chair is not for sitting in but for dancing with, for young girls from the Ivory Coast in their puberty initiation ites.

Saucers with holes in the middle are brass anklets, at one time worn by women as a sign of prestige and wealth. (As the anklets would require a blacksmith to remove them, women slept in them.) And huge gold earrings would constitute the entire bankroll of a woman from a nomadic group.

Carrying a medicinal powder in its chest cavity, a charm with a man's pointy face runs the gamut of materials: It is draped with an antelope horn, a gourd, a seed pod, a cocoon and cloth handles. But perhaps the oddest of materials here among the bone, gold, brass and forged iron, are some blue beads on a lovely necklace of brass bells and leopard claws. The beads came from melted-down bottles of Milk of Magnesia. -- Pamela Kessler.

HISTORY, CONTEXT AND MATERIALS -- At the Museum of African Art through January 5, 1986.