A golden diadem or head clasp, which may have been worn as a crown, could provide the key to the royal lineage of a recently unearthed Hellenistic tomb that is generally hailed as one of the greatest archeological discoveries since World War II.

But is it the tomb of King Philip II of Macedonia, father of Alexander the Great? Or of a member of the royal family? A nobleman? Or warrior of the 4th century B.C.?

The tomb lacks inscriptions or portraits, and the diadem could be the most definitive evidence linking it to a king, thus vindicating the claims of Prof. Manolis Andronikos that it is the tomb of Philip, who was assassinated in 336 B.C.

Although few such discoveries gain universal acceptance, the Novermber find by Andronikos, in the farming village of Vergina, 35 miles southwest of here, has split the archeological world down the middle.

It has also engulfed the 58-year-old professor in controversy. He based his initial identification on discovery of five miniature ivory heads.

"This was a premature conclusion," said Prof. Photios Petsas, former head of the Greek Archeological Service in Macedonia, who, along with Andronikos, began excavating a 3d century B.C. palace at Vergina in 1937. "And the heads are certainly not definitive evidence . . . they may be works of art, but how can one verify that they are Philip and Alexander, Philip's parents and his fourth wife, on the basis of highly stylized figures which are only 2 1/2 centimeters high? Besides, these are in no way unique in archeology, and could have been placed in the tombs of warriors, nobles, members of the royal entourage . . . Very similar statuettes have been unearthed at Macedonian sites before."

"The most important thing is not whether this is or is not the tomb of Philip," Andronikos said in an interview. "What is important is that these are unique, extraordinary finds. The paintings, the gold, silver and ivory objects of the Hellenistic period which we have never seen before. These are of immense value to archeologists and historians . . . And I am just at the beginning of the excavation. I hope that it will yield even more."

The find includes two solid caskets, wighing 24 and 17 pounds, and 38 cases of objects fashioned from silver, ivory, bronze and gold.

Seventeen feet beneath an artificial mound of earth, Andronikos unearthed the tomb housing many of the finest examples of Hellenistic art.

They include what could be a royal scepter, gilt leggins, a golden arrow box, and a gold, silver and ivory shield. In addition, the find includes a tiny statuette of the Winged Victory and a delicate golden wreath of acorns and oak leaves, symbol of the god Zeus.

A scene climaxing a lion hunt, painted across the frieze, is believed to be the prototype of the famous Pompeii mosaic which, according to archaelogists, could prove definitively that monumental wall painting originated in Greece.

"The dating is absolutely accurate," said Andronikos, "between 350 and 320 B.C. We know this from red figure pottery which we discovered that was made no later than 320 B.C., and from the shape and design of a small oil lamp, made no earlier than 350 B.C. . . .

And with that I believe is archaelogical evidence that it is a royal tomb, more importantly that of a king, who else is there [buried] between 359 and 320? There are only Philip and Alexander - and Alexander was buried in Egypt. There are just no other kings!"

The strongest leader of the period, Philip - a warrior and womanizer who reigned from 360-336 B.C. - was assassinated at ancient Aigai, where he wa to attend the wedding of his daughter before embarking on the Persian campaign. He was succeeded by his son Alexander, 20, who implemented his father's plan.

"And I knew," Andronikos continued, "when we discovered pieces of iron belonging to the dressing of horses, and the charred ruins of a chariot atop the tomb, that this was no ordinary person, accord the burial of Homeric times."

"But I do have my doubts," he concluded. "If this diadem is not royal diadem - if the scepter is not a sceptor - well, then . . . Until I find an inscription, I shall continue to have doubts."

Compounding the enigma at Vergina is that fact that Andronikos is the first of the 30 Macedonian tombs unearthed in the area which was not plundered.

"What makes this tomb unique is that it was untouched," said Petsas. "But it is certainly not the most monumental Macedonian tomb we have discovered: Neither in scale, in grandeur, or in size. The interior is very poor and careless. And I do not accept Andronikos' explanation that this was due to a hasty burial, since those capable for the assassination could have included Alexander and his mother Olympias, Philip's bypassed wife. This is historical gossip, not sound historical judgment based on fact."

"The tomb is certainly very rich and very important, aristocratic and regal without a doubt, but I don't believe it's royal," said Prof. Colin Edmonson the the American School of Classical Studies. "Discard the scepter. That's a tendentious argument. It's a sceptor only if the tomb is royal. The diadem is the most convincing piece of evidence, but it was found outside the sarcophagus, which is rather curious, lying on the floor. And we simply don't know who wore the diadem; we have never seen one before."

"It is regularly represented on portraits of the kings of Macedonia," he continued, "but we have seen similar things on poets and playwights as well . . . And the star burst symbol found on the caskets - we know that of Macedonia, but its use was not re-this was the symbol of the royal house restricted to the royal house."