Opal (gem)

"The opal, symbol of hope, shines with all colours of the rainbow. It has the power to give glimpses of the future, and to aid those with weak sight. The opal has a special relationship with the lapis lazuli, the heavenly stone, a powerful talisman."

- The Belt of Deltora

The great Opal is the talisman of the Plains tribe and is held in the fifth medallion of the Belt of Deltora.

Powers
The Opal can give glimpses of the future when it is touched. It helps those with weak sight and has a special relationship with the Lapis Lazuli. The Opal is known to strengthen Opal dragons. Notably, the Opal is the only gem on the Belt of Deltora Lief has actually avoided touching (for fear of its visions) and has done so more than once.

Tales of Deltora
After the marriage of the Land of Dragons and Pirra, the ground had given up a wondrous gem to each of the tribes of the Land of Dragons. To the people of the Plains, this gem was the Opal. Hundreds of years afterwards The Opal bacem the fifth gem Adin added to his belt.

The Forests of Silence
Hundreds of years after Adin collected the Opal and put it along with the other gems into the Belt of Deltora, the Opal was taken from the belt by the Shadow Lord's Ak-Baba. The Ak-Baba took the gem to Hira in the plains territory and it was entrusted to the giant snake, Reeah. The gem was worn in a crown upon his head and it gave him visions of the future.

The City of the Rats
This is how Reeah knew Lief's name when the companions came searching for the gem. Upon obtaining the gem, Lief accidentally touched the Opal and it showed him a vision of the Shifting Sands. Lief resolved to not touch the Opal from that point, since the vision terrified him.

The Shifting Sands
Lief felt a strange pull during his times in the Shifting Sands, where he was lead, blindly towards the Hive. It was there he found the Lapis-lazuli and he realised that the Opal had been guiding him along due to the special connection the two gems share.

The Maze of the Beast
In order to find out where the Maze of the Beast lay, Lief built up the courage to touch the Opal again, despite his fear of what he would be shown. He was given a glimpse of the inside of the Maze of the Beast and the Amethyst's deadly guardian, the Glus.

The Sister of the South
Lief used the power of the Opal to heal Barda after he had been blinded by the Sister of the South. While doing so, the Opal showed him a vision of a dead landscape. At first everyone believed this to be the Shadowlands, but Lief later suspected it was Deltora after the grey tide was unleashed.

Anime
The only major difference in the anime was the second time Lief used it. Here, it was after the companions retrieved the Amethyst, rather than before. Lief touched the gem while sleeping, and was given a vision of Barda and Jasmine giving their lives willingly for him. This later came true when the three were trapped in the sorceress Thaegan's Mirror of Fear.

Trivia

 * Opal is a national gemstone of Australia.