When we think of money it's usually in terms of bullion, metal-backed, or fiat currencies because that's what's been common globally for thousands of years and standard in modern history. We're so used to it that we rarely think of other kinds of currency, but anything can be a store of value if people agree it is.
Around here they use (d66):
11 Measures of mercury in thick-walled glass ampules. If one breaks it's normal for the owner to scoop up the droplets, eat them, and refine the metal out of their bloodstream later.
12 Rechargable batteries and capacitors whose value depends on how much energy is stored inside at the moment. The vintage versions are coiled springs that are more valuable the tighter they're wound. They're rarer now but still accepted.
13 Units of fuel with prices commonly set in lux-seconds, BTUs, or mileage and occasionally in wattages or calories. Any type of fuel is usually acceptable but petroleum products are the most common. Flashy wallet jerry cans with carry slings and small secondary nozzles for accurately dispensing mL and fl.oz portions are popular accessories.
14 Alcohol. Any kind will do so long as it's drinkable, but value is based on alcohol content so people usually carry high-proof liquor for convenience's sake. There are cellar-banks that offer safe deposit casks but it's not wise to keep too much of your money in them since it's vulnerable to long-term evaporatory pressure.
15 Pure potable water. Prices are set in milliliters and liters and everyday purchases are made directly with water carried in canteens or flasks. Larger transactions are handled with bronze ring-tokens that represent water stored in a central cistern. People sometimes mortgage the water in their bodies if they're desperate, but it trades at a lower rate set for contaminated, gray, or brackish water.
16 Salt exchanged as chunks of raw rock salt, large coarse grains, fine-ground crystals ready to eat, or pressed into different shaped cakes and bricks. Its value is always based on weight and purity.
21 Grain. Any of the common staples, all traded by volume with exchange rates to account for the size differences between the various types. Some people add a surcharge to accept types of grain they don't prefer, it's legal but frowned on. Some merchants may offer a discount if you pay with a grain they can directly use, but it's rude to ask for one.
22 Tea as loose rolled leaves or compressed in long, narrow bricks. Reputable trade tea is always plain with scents and flavorings left for the owner to add if they decide to brew it. Scented trade tea is highly suspicious and likely trying to disguise spoiled leaves.
23 Ounces of sugar. It doesn't matter what the sugar's refined from but higher purity samples carry a premium. The most common sources are sugar cane, beets, crystallized honey, and maple sugar. It's the only currency accepted for paying tax-tithe-tribute to the Formic Empress.
24 Dragon's blood resin in rough chunks, granules, and ground powder. It's measured in drams and commonly carried in pre-measured packets or twists of oiled paper. There are strict limits set on how much resin can be collected each season to avoid harming the dragon trees.
25 Links and lengths of chain. The links are all the same size and joined into chains for convenience. Different metal chains have different values and people carry wire cutters and pliers to snip off links as needed.
26 6" lengths of heavy gauge iron wire with each end hammered into a flattened paddle shape. Each piece is slightly irregular from how they're manufactured, but they all weigh the same amount and are dipped in beeswax to protect against rust. They're usually carried and exchanged in bundles and even small purchases take at least two since it's unlucky to spend just one.
31 Hours of labor represented by hand-shaped bisque fired terracotta tokens. Can be redeemed with any citizen for normal work in half hour, hour, and six hour increments.
32 Favors, with the fair value of each exchange negotiated between individuals. There's no official record or enforcement of the agreements, but everyone will know if you strike an unequal deal or break your word.
33 Increments of time, shaving moments off the end of your lifespan with each purchase. Normal points are set in second, minutes, and hours while expensive things range into weeks, months, years, and sometimes even decades. There aren't physical tokens or indications of the time left, so accurate accounting is vital.
34 Souls, either bound in vessels and traded directly or represented by polished rosewood chits linked to spiritually binding IOUs. Animals' souls are used for most transactions but people's souls get traded fairly often and can't be fully redeemed until after their death. Every person has the right to buy their soul back in a 1:1 exchange as long as they can find the person holding their chit.
35 Lace and ribbons with specific weave, color, and knot patterns reserved for cash yardgoods. They're kept wound on spools and cards, tied in tassels, or stitched loosely onto clothes so they're secure but can be removed easily. Prices are set in inches and while long uncut pieces aren't worth more than an equal yardage of short pieces, there is a prestige and preference attached to them.
36 Sewing needles and pins. Their value is tied to their use as tools, not the worth of their material. Steel is the most common for everyday business with nickle, silver, and gold-plated varieties carrying a slight premium because they don't rust. Bone, thorn, and wood needles are still used but reserved for certain ceremonial purchases.
41 Handmade glass beads. They come in all shapes and colors, but the most popular type are thick opaque rondelles in black, shades of orange, and occasionally pink and red. They're mainly made in solid colors or lightly marbled swirls, if there are any patterns it'll be strip or chevron motifs only.
42 Molded glass figurines in five color-shape denominations. There are 5 black rats to 1 lilac owl, 4 owls to 1 red cat, 3 cats to 1 blue man, and 2 men to 1 amber goblet. A slice of pizza costs 1 rat and 3 blue men is enough to see a concert.
43 Hexagonal porcelain tiles with debossed lines running from corner to corner across both faces so they can easily be snapped into halves, thirds, or 6 triangular segments. They're glazed a distinctive peacock blue-green. The glaze's formula is a royal secret and trying to replicate it carries a minimum 12-years prison sentence.
44 Polished cushion-shaped mother of pearl discs the size and weight of go stones. The shape and smooth finish of the pieces is more important to their value than the nacre's color and shine. Even heavily circulated pieces will have been carefully protected and only have a few fine scratches at most. One disc is enough to buy a day's food and lodging.
45 Baroque freshwater pearls, the more irregular the shape and deeper the color the more prized they are. They're exchanged in momme. 1 momme is enough to outfit and provision an adventurer for a week.
46 Translucent sky blue snail shells with iridescent red stripes. The snails grow slowly, taking 7 to 8 years to reach their adult size of half an inch long and start developing the red stripes. Unstriped shells are used as children's play money.
51 The rounded chickpea-sized teeth of a titan parrotfish. There are hundreds of them in each bus-sized monster's mouth, but landing one during their triannual migrations takes the concerted effort of an entire village.
52 Brachiopod fossils mined from the local shales and collected from riverbeds by a militant order of prospector-priests. Each fossil is graded based on its age, size, condition, and the site where it was found; then inscribed with identifying serial glyphs. Origin is the most important factor and specimens from holy sites are exponentially more valuable than fossils mined from unconsecrated ground.
53 Polished agate bangles produced by a dedicated guild of hardstone carvers. The traditional design is a slender vine-carved band 2" in diameter. Children can wear them easily but most adults carry them on braided cords. The guildmaster is heir to the artistic lineage and has the right to change the bangles' design every 14 years, but none have yet.
54 Uncut sapphires fresh from the mines and recovered from alluvial deposits. Prices are set in carats and higher for outsiders, often by orders of magnitude but always at least triple what a local would pay.
55 Human finger and toe bones that are used until they're polished smooth with an ivory-like patina. New bones come into circulation regularly and are accepted without comment, but people who only spend fresh bones are suspicious and distasteful.
56 Precious coral branches and twigs. The coral is entirely extinct in the region from overharvesting so the supply is finite. It's priced by weight and usually exchanged in the form of short broken segments. Intact specimens with complex branches are very rare and kept as investment pieces or heirlooms, not spent.
61 Feathers either loose as individual pieces or woven into belts, cloaks, and blankets. Only green, blue, black, and white feathers have value and there are harsh hunting laws in place to stabilize that value and protect the kingfisher, hummingbird, and corvid populations.
62 Mustelid pelts. Furs are valued by size with 6 skins from a small species worth 1 of a medium-sized species, and 6 medium skins worth 1 of a large animal's. Ermine, stoat, mink, marten, and otter pelts are prized while no one really wants to accept ferret or wolverine skins.
63 Dried beetles preserved in sealed vials of clear oil. Their iridescent metallic carapaces darken from a translucent pearl white to silver, pale gold, jade and emerald green, and black as they age. Deeper shades are more valuable.
64 The brilliant chrome chrysalises of the orange-spotted tiger clearwing butterfly. Each month they're ritually collected from the civic nightshade gardens by children, baked to preserve them, then distributed equally among all the members of the community. They're delicate and usually carried in hinged cases lined with cotton batting.
65 Live corn snakes. Each city-state has its own signature breed but the different color morphs are accepted the same everywhere. Everyday purchases are made with freshly hatched and young specimens while adults are reserved for larger purchases. Breeding females are the most valuable but people usually hang on to them. The money supply is kept stable by the cities' most common cuisine: Corn snakes.
66 Viable seeds and cuttings for propagation. Fruit, vegetables, and flowers are the most common but all types of plants circulate, including more difficult species like trees and cacti. They're not required crops for survival anymore since reconstituted algal mass and synthesized protein provides enough nutrition for everyone, but people still love plants. Having the resources, space, and skill to actually grow them underground is a status symbol.
14 Alcohol. Any kind will do so long as it's drinkable, but value is based on alcohol content so people usually carry high-proof liquor for convenience's sake. There are cellar-banks that offer safe deposit casks but it's not wise to keep too much of your money in them since it's vulnerable to long-term evaporatory pressure.
15 Pure potable water. Prices are set in milliliters and liters and everyday purchases are made directly with water carried in canteens or flasks. Larger transactions are handled with bronze ring-tokens that represent water stored in a central cistern. People sometimes mortgage the water in their bodies if they're desperate, but it trades at a lower rate set for contaminated, gray, or brackish water.
16 Salt exchanged as chunks of raw rock salt, large coarse grains, fine-ground crystals ready to eat, or pressed into different shaped cakes and bricks. Its value is always based on weight and purity.
21 Grain. Any of the common staples, all traded by volume with exchange rates to account for the size differences between the various types. Some people add a surcharge to accept types of grain they don't prefer, it's legal but frowned on. Some merchants may offer a discount if you pay with a grain they can directly use, but it's rude to ask for one.
22 Tea as loose rolled leaves or compressed in long, narrow bricks. Reputable trade tea is always plain with scents and flavorings left for the owner to add if they decide to brew it. Scented trade tea is highly suspicious and likely trying to disguise spoiled leaves.
23 Ounces of sugar. It doesn't matter what the sugar's refined from but higher purity samples carry a premium. The most common sources are sugar cane, beets, crystallized honey, and maple sugar. It's the only currency accepted for paying tax-tithe-tribute to the Formic Empress.
24 Dragon's blood resin in rough chunks, granules, and ground powder. It's measured in drams and commonly carried in pre-measured packets or twists of oiled paper. There are strict limits set on how much resin can be collected each season to avoid harming the dragon trees.
25 Links and lengths of chain. The links are all the same size and joined into chains for convenience. Different metal chains have different values and people carry wire cutters and pliers to snip off links as needed.
26 6" lengths of heavy gauge iron wire with each end hammered into a flattened paddle shape. Each piece is slightly irregular from how they're manufactured, but they all weigh the same amount and are dipped in beeswax to protect against rust. They're usually carried and exchanged in bundles and even small purchases take at least two since it's unlucky to spend just one.
31 Hours of labor represented by hand-shaped bisque fired terracotta tokens. Can be redeemed with any citizen for normal work in half hour, hour, and six hour increments.
32 Favors, with the fair value of each exchange negotiated between individuals. There's no official record or enforcement of the agreements, but everyone will know if you strike an unequal deal or break your word.
33 Increments of time, shaving moments off the end of your lifespan with each purchase. Normal points are set in second, minutes, and hours while expensive things range into weeks, months, years, and sometimes even decades. There aren't physical tokens or indications of the time left, so accurate accounting is vital.
34 Souls, either bound in vessels and traded directly or represented by polished rosewood chits linked to spiritually binding IOUs. Animals' souls are used for most transactions but people's souls get traded fairly often and can't be fully redeemed until after their death. Every person has the right to buy their soul back in a 1:1 exchange as long as they can find the person holding their chit.
35 Lace and ribbons with specific weave, color, and knot patterns reserved for cash yardgoods. They're kept wound on spools and cards, tied in tassels, or stitched loosely onto clothes so they're secure but can be removed easily. Prices are set in inches and while long uncut pieces aren't worth more than an equal yardage of short pieces, there is a prestige and preference attached to them.
36 Sewing needles and pins. Their value is tied to their use as tools, not the worth of their material. Steel is the most common for everyday business with nickle, silver, and gold-plated varieties carrying a slight premium because they don't rust. Bone, thorn, and wood needles are still used but reserved for certain ceremonial purchases.
41 Handmade glass beads. They come in all shapes and colors, but the most popular type are thick opaque rondelles in black, shades of orange, and occasionally pink and red. They're mainly made in solid colors or lightly marbled swirls, if there are any patterns it'll be strip or chevron motifs only.
42 Molded glass figurines in five color-shape denominations. There are 5 black rats to 1 lilac owl, 4 owls to 1 red cat, 3 cats to 1 blue man, and 2 men to 1 amber goblet. A slice of pizza costs 1 rat and 3 blue men is enough to see a concert.
43 Hexagonal porcelain tiles with debossed lines running from corner to corner across both faces so they can easily be snapped into halves, thirds, or 6 triangular segments. They're glazed a distinctive peacock blue-green. The glaze's formula is a royal secret and trying to replicate it carries a minimum 12-years prison sentence.
44 Polished cushion-shaped mother of pearl discs the size and weight of go stones. The shape and smooth finish of the pieces is more important to their value than the nacre's color and shine. Even heavily circulated pieces will have been carefully protected and only have a few fine scratches at most. One disc is enough to buy a day's food and lodging.
45 Baroque freshwater pearls, the more irregular the shape and deeper the color the more prized they are. They're exchanged in momme. 1 momme is enough to outfit and provision an adventurer for a week.
46 Translucent sky blue snail shells with iridescent red stripes. The snails grow slowly, taking 7 to 8 years to reach their adult size of half an inch long and start developing the red stripes. Unstriped shells are used as children's play money.
51 The rounded chickpea-sized teeth of a titan parrotfish. There are hundreds of them in each bus-sized monster's mouth, but landing one during their triannual migrations takes the concerted effort of an entire village.
52 Brachiopod fossils mined from the local shales and collected from riverbeds by a militant order of prospector-priests. Each fossil is graded based on its age, size, condition, and the site where it was found; then inscribed with identifying serial glyphs. Origin is the most important factor and specimens from holy sites are exponentially more valuable than fossils mined from unconsecrated ground.
53 Polished agate bangles produced by a dedicated guild of hardstone carvers. The traditional design is a slender vine-carved band 2" in diameter. Children can wear them easily but most adults carry them on braided cords. The guildmaster is heir to the artistic lineage and has the right to change the bangles' design every 14 years, but none have yet.
54 Uncut sapphires fresh from the mines and recovered from alluvial deposits. Prices are set in carats and higher for outsiders, often by orders of magnitude but always at least triple what a local would pay.
55 Human finger and toe bones that are used until they're polished smooth with an ivory-like patina. New bones come into circulation regularly and are accepted without comment, but people who only spend fresh bones are suspicious and distasteful.
56 Precious coral branches and twigs. The coral is entirely extinct in the region from overharvesting so the supply is finite. It's priced by weight and usually exchanged in the form of short broken segments. Intact specimens with complex branches are very rare and kept as investment pieces or heirlooms, not spent.
61 Feathers either loose as individual pieces or woven into belts, cloaks, and blankets. Only green, blue, black, and white feathers have value and there are harsh hunting laws in place to stabilize that value and protect the kingfisher, hummingbird, and corvid populations.
62 Mustelid pelts. Furs are valued by size with 6 skins from a small species worth 1 of a medium-sized species, and 6 medium skins worth 1 of a large animal's. Ermine, stoat, mink, marten, and otter pelts are prized while no one really wants to accept ferret or wolverine skins.
63 Dried beetles preserved in sealed vials of clear oil. Their iridescent metallic carapaces darken from a translucent pearl white to silver, pale gold, jade and emerald green, and black as they age. Deeper shades are more valuable.
64 The brilliant chrome chrysalises of the orange-spotted tiger clearwing butterfly. Each month they're ritually collected from the civic nightshade gardens by children, baked to preserve them, then distributed equally among all the members of the community. They're delicate and usually carried in hinged cases lined with cotton batting.
65 Live corn snakes. Each city-state has its own signature breed but the different color morphs are accepted the same everywhere. Everyday purchases are made with freshly hatched and young specimens while adults are reserved for larger purchases. Breeding females are the most valuable but people usually hang on to them. The money supply is kept stable by the cities' most common cuisine: Corn snakes.
66 Viable seeds and cuttings for propagation. Fruit, vegetables, and flowers are the most common but all types of plants circulate, including more difficult species like trees and cacti. They're not required crops for survival anymore since reconstituted algal mass and synthesized protein provides enough nutrition for everyone, but people still love plants. Having the resources, space, and skill to actually grow them underground is a status symbol.