Pikmin (Series)

The Pikmin franchise features a small batch of coins, with all of them originating in Pikmin 2, and one of them going on to have a minor role in Pikmin 3.

Pokos
Pokos are the main currency used on the planet Hocotate (and presumably Koppai). Olimar and Louie are tasked with obtaining ten thousand Pokos to repay Hocotate Freight's debt at the beginning of Pikmin 2, and set off back to the planet PNF-404 to collect treasure to sell. When in caves, monster corpses can also be sold for a small amount of Pokos, instead of being used to produce more Pikmin like they are on the surface.

Pokos play a very minor role in Pikmin 3, appearing as the points system in the "Collect Treasure!" bonus stages, despite not being mentioned by name. They also have an updated design compared to their Pikmin 2 appearance, now looking a lot like a coin from the Mario series.

Pikmin 3 Deluxe features a new Side Stories mode where Pokos are mentioned and used quite similarly to the stages in the Wii U version. In this mode, Olimar and Louie are tasked with collecting more Pokos to save Hocotate Freight from yet another debt.

Treasures
Pikmin 2 also features some coins that can be found as treasures on PNF-404.

Lustrous Element
The Lustrous Element is found in the Hole of Heroes and is dropped by the Pileated Snagret after being defeated. It is tied with the four Titan Dweevil treasures as the 2nd most valuable treasure in the entire game, being worth one thousand Pokos. It is actually based on a golden dollar coin, a gold coin that was struck as a regular issue by the United States Bureau of the Mint from 1849 to 1889.

Olimar's journal
“This rare, alien metal doesn't exist on Hocotate. When I gaze at it, I'm gripped with an overpowering sense of greed. On Hocotate, there is a valuable metal with a stunning sheen that has a similar effect. Perhaps this alluring metal is responsible for many of this planet's woes.”

Sales Pitch
“Such radiance! Such shine! Like magic, this product stimulates greed in all intelligent life-forms. Bring your wallets and gather around, buyers!”

Mirrored Element
The Mirrored Element is found in the Dream Den. It is worth three hundred Pokos. It is based on the silver Morgan dollar coin, which was minted from 1878 to 1904, in 1921, and as a special non-circulating coin in 2021.

Olimar's journal
“Talking to the boss makes me crave the power to order people around. He just sits on his haunch all day, barking out wildly irrational requests. Arrgg... When will it be my turn to be the boss?”

Sales Pitch
“All reason flies in the face of this sparkle. It's not flashy, but it still inspires avarice!”

Unknown Merit
The Unknown Merit is found in the Bulblax Kingdom and is dropped by a Wollywog. It is worth one hundred Pokos. It is based on a wadōkaichin coin, the oldest official Japanese coinage, first minted on 29 August 708 on order of Empress Genmei.

Olimar's journal
“Detailed analysis has revealed that this artifact is extremely ancient. It's obviously an important archeological discovery, but the salesman in me is more interested in its monetary value! Maybe I'll get the best of both worlds by selling it to a museum.”

Sales Pitch
“Decades of toil with nose to the grindstone. Insulting orders swallowed without a hiccup. Such is the life of a salaried man. His name will not be remembered. His family will not understand. But if the results bear out his efforts, that is enough. Now, nose to the grindstone, drone!"

Trivia

 * In the animated Pikmin short, there was a cute reference to the Mario franchise in the form of a Pikmin going through a green pipe full of coins. However, the Pikmin did not collect the coins on contact with them. This confirms that Pikmin are useless fucking creatures who are unable to collect even the most basic coins.