VATICAN CITY (AP) -- It's not the Holy Grail, but for fans of "The Da Vinci Code'' and its tantalizing story line about the Knights Templar, it could be the next best thing.

Ignored for centuries and found in the Vatican secret archives in 2001, a parchment about the early 14th-century heresy trial of the ancient Christian order is the basis of a limited edition volume being published with an euro5,900 (US$8,375) pricetag.

According to the Vatican archives Web site, the parchment shows that Pope Clement V initially absolved the Templar leaders of heresy, though he did find them guilty of immorality, and planned to reform the order.

But pressured by French king Philip IV (Philip the Fair), Clement later reversed his decision and suppressed the order in 1312.

Only 799 copies of the 300-page volume "Processus Contra Templarios'' (Latin for "Trial against the Templars'') are for sale -- each priced at euro5,900 (US$8,377), Scrinium publishing house, which prints documents from the Vatican's secret archives, said Friday.

An 800th copy would go to Pope Benedict XVI, said Barbara Frale, the Vatican archives researcher who found the parchment tucked away in the archives in 2001.

The Vatican will hold a news conference about the publication on Oct. 25.

The order of knights, which ultimately disappeared because of the heresy scandal, recently captivated the imagination of readers of the best-seller "The Da Vinci Code,'' which linked the Templars to the story of the Holy Grail.

The Vatican work reproduces the entire documentation of the papal hearings convened after Philip arrested and tortured Templar leaders in 1307 on charges of heresy and immorality.

The military order of the Poor Knights of Christ and of the Temple of Solomon was founded in 1118 in Jerusalem to protect pilgrims in the Holy Land after the First Crusade.

As their military might increased, so did Templar wealth, as the knights went on to run a primitive banking system. After they left the Middle East with the collapse of the Crusader kingdoms, their power and secretive ways aroused the fear of European rulers and sparked accusations of corruption and blasphemy.

The "Parchment of Chinon'', nearly 1 meter (yard) wide -- "the size of a small tabletop'', as Frale put it -- details the 1308 decision by Clement to save the Templars and their order.

Frales told The Associated Press in a telephone interview from her home in Viterbo, north of Rome, that the parchment in Latin probably had been ignored because the 1628 catalog entry was "too vague.''

"Unfortunately, there was an ... error in how the document was described,'' Frale said in a telephone interview from her home in Viterbo, north of Rome. "More than an error, it was a little sketchy.''

She described the parchment, with its writing in Latin, in remarkably good condition considering its 700 years.

The parchment had last been consulted at the start of the 20th century, Frale said, surmising that its significance must have not have been realized then.

Frale said she was intrigued by the 1628 entry because, while it apparently referred to some minor matter, it noted that three top cardinals, including the right-hand man of Clement, Berenger Fredol, had made a long journey to interrogate someone.

"Going on with my research, it turned out that in reality it was an inquest of very great importance'' on behalf of the pope, Frale said. Fredol "had gone to question the Great Master and other heads of the Templars who had been segregated, practically kidnapped, by the king of France and shut up in secret in his castle in Chinon on the Loire.''

Jacques de Molay, Grand Master of the Templars, was burned at the stake in 1314 along with his aides. Surviving monks fled. Some were absorbed by other orders; over the centuries, various groups have claimed to have descended from the Templars.

Clement "was a hostage in French territory'' on the eve of what historians would call the Avignon period of popes, Frale said.

The cardinals reached the conclusion "that it wasn't a real and true heresy,'' Frale said of what was written in the parchment.

"There were a lot of faults in the order -- abuses, violence ... a lot of sins, but not heresy,'' said the researcher.

Clement, said Frale, "wanted to deeply purify'' the order of knights, aiming at a complete reform.

Among the violence was the practice of forcing new recruits to "reject Christ in words and spit on the Cross,'' in imitation of the violence suffered by knights when captured by Muslims, Frale said. New members were even kicked and punched if they refused to undergo this kind of hazing, she said.

Philip had "confiscated all the wealth of the order, which he used to pay his debts,'' said Frale, who has written three books about the Templars. "Now, had the (order) survived, it's clear that Philip the Fair would have had to give back all'' the wealth.

"But the king of France had already spent it,'' Frale said.

Associated Press Writer Ariel David contributed to this report.