I was watching Shoddycast's video on the value of bottle caps as currency in Fallout 4 today, and after having read part of Brandon Sanderson's Words of Radiance earlier this morning, my mind started to wander to the possibilities of currency far stranger than either bottle caps or the Stormlight-infused glass "spheres" with gemstones inside them seen throughout Roshar. Is it possible for food or organic materials and animal byproducts to be used as a practical currency?
Which leads me, of course, to slimes and honey. Honey is sweet, nutrient dense, and has a very long shelf-life. And slimes are the quintessential fantasy trash mob. Why not combine the two, and make honey (or perhaps some sort of similarly sticky-sweet "slime milk" or gel) the common currency of a fantasy world where these creatures exist? By themselves, they already fulfill many of the qualities of a good currency according to the definitions set by the Shoddycast video:
-They are "shelf-stable" (honey lasts a long, long time, and presumably so does slime)
-They are rare, but not too rare (since slimes are wild monsters and must be killed to harvest their byproducts)
-They're easy to identify (usually because they're brightly colored and, indeed, slimey)
-They're hard to fake (taking into account their distinct color, taste and texture compared to other foods and animal byproducts)
However, the problems I'm seeing are that slimes fail in a few other major categories. They aren't easy to carry around or turn into money (you can melt metal into coins but what do you do with a blob of slime?).
While slimes aren't usually considered good livestock or farm animals in most fantasy settings. The possibility of someone attempting slime farming or someone stumbling into a huge number of slimes at once in the wild makes runaway inflation a distinct possibility. Unlike metal or minerals, which tend to be a finite resource, organic materials like honey or a slime's slime can always be reproduced in large quantities after loss or consumption. Such is their nature.
Are there any ways to deal with these problems that could justify honey or slime as a practical currency, or will metal and gemstones always be a better "store of value" than organic materials?