PS Vita Lego:Lord of the Rings game

Bubba and I are currently playing through this Lego game on the Vita. However, we're both a bit unsure as to what collecting the gold and silver small coin type lego pieces does! Anyone have any ideas as to what they are?

Thanks!

I've only played it on the Wii, but it does two things:

If you're collecting the pieces during the open-world between stages, you can save them up to buy new characters to use in open play.

If you're collecting them during the levels, if you collect it until the meter at the top of the screen is flashing, you'll be "True Adventurer". This gives you an extra mithril block at the end of the level to use in Bree for crafting items. Any coins you win during the level can also be applied to buying new characters.

Just want to say Lego Lord of the Rings is amazing and walking from the Shire to Mount Doom is a lot of fun. As is marching into Bree as Sauron with Saruman in tow for a drink at the Prancing Pony. The locals aren't particularly welcoming.

I bought this a few months ago for Wii & only played a wee bit. :D

I should try to play some more.