Kinda popped up on the test server. I like the idea -- but you've twisted the market value a little.
Duck: 8 hr x2 buff for 200 guild coins -- (value 8gc) -- 25 guild coin / gc
Pasta: 12 hr x2 buff for 300 guild coins -- (value 12gc) -- 25 guild coin / gc
Scarecrow: 10 hr x3 buff for wheatfield for 600 guild coins -- (max 750 extra wheat -- value 16) -- 37.5 guild coin / gc
Marble: 100 marble for 100 guild coins -- (value 3gc) -- 33.3 guild coin / gc
Pirates: 2000 guild coins -- (value 200gc) -- 10 guild coin / gc
Jolly geo: 4000 guild coins -- (value 800gc) -- 5 guild coin / gc
I've got issues with this:
1) The market value of these items puts guild coins varying from 3% to 20% of the value of gold coins -- which is a large varience and should be much more stable.
2) I assume that guild coins will be equally as difficult or harder to obtain than gold coins. If this is the case, the players will all feel ripped off by this new market.
2) 4000 coins to 300 gems (direct coin to gem relationship on the jolly geologist) sets the gem-to-coin ratio at 13.3:1 (when current market value has them around 3:1) -- this would devalue our currency quite sharply.
Suggestions:
New pricing ( Duck 40, Pasta 60, Scarecrow 50, Marble 20, Pirates 1000, Jolly 4000 )
Replace marble with granite ( 50 granite for 400 coins )
Golden Parrots ( parrot for 900 coins )
Copper Diviner ( 500 copper depo for 200 coins )