The recently unearthed stone carving known as the Miami Circle opens a window to the long-obscured, mysterious past of the Tequesta tribe that lived at the mouth of the Miami River when Ponce de Leon arrived in 1513.

It is a window that could slam shut again if the property's developer begins moving the Circle this week, as planned, and starts construction on the rest of the site Feb. 26. Once again, the Tequesta's heritage could be erased from the landscape.

"They were the ancestral occupants of Miami and I think current occupants have an obligation to them, " said Dr. William Sturtevant, curator of ethnology at the Smithsonian Institution in Washington, D.C., who has studied the Tequesta. "There's very little information about them and that's one reason the archaeology at the site should be completed."

Isolated and enigmatic, little known and little appreciated, the Tequesta hunted whales and alligators. They harvested shellfish and berries. They worshiped animals and the sun.

They sought, generally unsuccessfully, to avoid subjugation by other native groups and contact with European explorers and missionaries. The Tequesta and related neighbors ranged through what would become Miami-Dade and Broward counties for hundreds of years, but their population never exceeded several thousand. Still, they dominated much of southeast Florida. The place now known as Miami was called Tequesta (sometimes spelled Tekesta or Chequescha) when Europeans arrived.

Two hundred years later, the Tequesta were gone - ravished by European disease, enslaved by other native groups, leaving behind scant evidence of their existence.

Until now.

IMPORTANT DISCOVERY

The 38-foot-diameter Miami Circle, which seems to be carefully aligned with points on the compass, today is recognized worldwide as an important discovery. Miami-Dade archaeologists found it while exploring a construction site just east of the Brickell Avenue bridge, across the river from the Dupont Plaza Hotel.

Developer Michael Baumann, financed by several unions, plans to build a towering residential and commercial development on the valuable site. A garage would sit where the Circle now rests.

He has allowed archaeologists to explore a limited portion of the 2.2-acre site, but says they must leave by Feb. 26, when construction will begin. Baumann plans to slice the Circle from the bedrock, cut it in 28 to 30 pieces and move it to a museum or other refuge.

That does not please or satisfy many experts and other activists.

"Preservation is one thing, but it isn't going to tell us much to save the holes in the rock that have so far been recovered, " Sturtevant said. "What is necessary is to do a careful archaeological excavation of the whole area."

DEEPER MYSTERIES

At the same time, each discovery seems to deepen the mysteries enveloping the Tequesta.

Many experts believe - but are not certain - that the Tequesta created the stone formation and that it might have been a sacred temple or ceremonial site.

Robert Carr, lead archaeologist at the site, and other experts say the Tequesta were technologically capable of digging into the limestone bedrock. Experiments have proven that a sharpened stone or shell, attached to a wooden stick, can penetrate the limestone's crust and create a hole.

A few years ago in West Broward, Carr found a thin branch tipped by a large, sharpened 500-year-old shell. It was a canoe-carving tool used by the Tequesta.