Okay, disregarding the unit of measurement (pounds, dollars, yen, whatnot) take a slug of given size and produce fractional monetary values by producing wedges of a size proportional to the value of the wedge. So a half dollar/pound/whatnot is half a circle, a quarter unit is a quarter circle, etc. Very pieces of eight and all that.

Now make the pieces interlocking, so one can produce a coin of any given value below the whole unit (unlike concentric coins). Individual values are easy to determine for the sightless and slugs of different diameter or thickness can be used for different base values ($1 slug, $10 slug, $100 slug, etc). The individual pieces pose less of a choking hazard to children, too (though there _is_ a stabbing issue to contend with).

Coin-operated machines would have to be retrofitted, but the upshot is that a coin of a given value will always be a certain percentage of the whole; regardless of how it's assembled.

Individual wedges could be constructed of different materials or made otherwise visually distinctive, though that's not required.
-- phoenix, Jul 22 2003

interesting reading - 8th of 8? http://www2.uah.es/asi/amcana/DOLLAR.HTM
[po, Oct 05 2004, last modified Oct 06 2004]

Concentric coins http://www.halfbake.../Concentric_20coins
The inspiration. [phoenix, Oct 05 2004]

you jest, rave.
-- po, Jul 22 2003


[ravenswood] et al: Last sentance, first paragraph. What, you think I don't give props?

Oops, forgot links.
-- phoenix, Jul 22 2003


What the hell do you want with a $100 slug? Can it write with its trail or something?
-- chud, Jul 22 2003


You could overcome the stabbing issue by rounding off the ends.

How about issuing slightly twisted coins, so that they assemble into a close-fitting helix. So, if I had £2.20, I could snap the coins together to form a helix of 2-and-a-fifth revolutions.
-- sandfly, Jul 22 2003


So [sandy], is that a 10 pound helix in your pocket or are you just happy to see me?
-- bungston, Jul 22 2003



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