The Clava Thessara Infinitas, or "Key to Infinite Treasure," is an Ancient tablet, a treasure map of sorts, which, according to legend, will allow he who possesses it entry to a vast storehouse of riches hidden away by the Ancients prior to their ascension. Athena and Qetesh had once partnered to search for the legendary treasure, but although they never found the tablet or the code to decipher it, Qetesh wanted Athena to believe that she had taken possession of it, and the two became bitter rivals.
Athena believed that Qetesh had found the tablet, although she had not deciphered it, and after Qetesh's symbiote had been removed from Vala, Athena used her connections within the Trust on Earth to kidnap Vala. Her intention was to locate the tablet and the code by using memory recall technology to probe Vala's subconscious for remnants of Qetesh's suppressed genetic memories still buried in Vala's mind. Although Vala was subjected to the painful memory probe, the facility was raided by the SGC and Vala escaped before any memories were uncovered.
At first Daniel believed that the Clava Thessara Infinitas might have been a hoax, but as he investigated further, he found Athena's research on the subject quite compelling. After cross referencing Athena's research with the Abydos cartouche, Daniel was able to generate a gate address that was a possible location of the treasure, and SG-1 investigated P4M-328. On the planet, SG-1 found a museum of Goa'uld artifacts, and they were unwittingly involved in a hostage situation, however no trace of the Clava Thessara Infinitas was discovered.
Although they had not recovered the treasure, SG-1 used the Clava Thessara Infinitas as a lure to capture Adria. Because Adria could sense the truth in one's mind, Vala volunteered to have a false memory implanted in her mind using the Galaran memory implant device. In this memory, the Clava Thessara Infinitas appeared as it did in ancient documents, as a stone tablet in the shape of a disc with a square hole at its center and random Ancient symbols and stargate glyphs etched into it. Vala had dreamed that the address of the treasure was made of the six symbols intersected by a horizontal infinity symbol superimposed on the disc: 14-21-16-11-30-7. However, an investigation led only to an ambush and no treasure was found. A second dream revealed a new address using a vertical infinity symbol: 26-20-35-32-23-4. Vala's implanted dream convinced Adria that the treasure would be found at the second address, and together they gated to the planet, expecting to claim the Ancient treasure for themselves, only to find SG-1 waiting on the planet to capture Adria.
SG-1 has been unable to identify the true location of the Clava Thessara Infinitas, neither the tablet nor the treasure has been recovered, and there is still no clear indication of what the Ancient storehouse actually contains.
Cross Reference: Ancients, Athena, Memory Implant Device, P4M-328, Qetesh
Episode Reference: Memento Mori, Bad Guys, Dominion
Stargate coordinates from the first implanted dream: 14-21-16-11-30-7
Stargate coordinates from the second implanted dream (site of Adria's capture): 26-20-35-32-23-4