Treasure has finally been found on The Curse of Oak Island — in the form of a brooch containing a 500-year-old faceted red gemstone.

The breakthrough discovery was made on the penultimate episode of the History show’s fifth season, being uncovered by metal-detecting expert Gary Drayton in an area to the north of the Nova Scotian island.

The rear part of the brooch was uncovered first, followed by a second part featuring the gemstone set in metal. Both items were found in the same location after being picked up using a hand-held metal detecting device.

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They were dug out of the ground by Rick Lagina, who along with brother Marty leads the treasure hunt on Oak Island. It was initially believed the stone could possibly be a ruby, but it was later revealed to be a 400- to 500-year-old rhodolite garnet. It has at least 11-12 facets.

The Season 5 finale showed Drayton revealing its age and what kind of stone it was. He said: “I took the gem to a gemologist — it’s a 400 to 500 year old stone.” If that is correct, it would mean the gemstone dates from the 1500s.

The discovery came on Lot 8 of the island’s 32 lots and in reality took place towards the end of 2017, while the team were carrying out their final searches on the island before Canada’s harsh winter set in. It was found on the same lot that a decorative keyplate was uncovered on the previous episode of the show.

The brooch’s discovery came moments after Gary Drayton and Rick Lagina also discovered what was believed to be a military cuff button dating from around 1780 to 1820.

Initially only the back plate of the ornate but visibly aged brooch was discovered, with the pair unable to locate the gemstone that formed the rest of it. They decided to leave the small hole they had dug open in case they wanted to return later with a sifting device.

However, in a lucky twist just as they were walking away Drayton picked up another signal with his metal-detecting device.

It turned out to be the circular piece of metal containing the unevenly-faceted stone. The pair were visibly blown away by the discovery, with Drayton, from Grimsby in England, describing it as a “bobby-dazzler” — a British phrase for something considered remarkable.

It was speculated that the brooch could be part of the lost treasures of Marie Antoinette, the last Queen of France, which are one of the many things that treasure-hunters believe could be buried on Oak Island.

Former President Franklin D. Roosevelt previously took a keen interest in the treasure hunt on Oak Island due to that particular theory.

The rhodolite garnet’s discovery follows that of a lead cross from the Middle Ages discovered by Drayton earlier in the season.

Other interesting finds on the show in Season 5 have included human bones, pearlware pottery and book binding discovered in the island’s so-called Money Pit area.

The penultimate episode also saw the re-discovery of a “u-shaped structure” under the beach at the island’s Smith’s Cove. It was previously found by treasure-hunters Dan Blankenship and David Tobias in the 1970s, but its true purpose was never discovered.

The Curse of Oak Island airs Tuesdays at 9/8c on History.