The obvious precedent for a set of numerals like this are the Aegean numerals, U+10107..U+10118, which are also quite obviously derived from layouts of tallying sticks, and which have a units set 1-9 and a tens set 10-90 oriented at right angles to the 1-9 set. But the Aegean system used other counters for 100 and up, so there is not a problem of alternating values.
And historical examples of the Aegean numbers exist *primarily* (if not exclusively?) in written form, on clay tablets.
-- Curtis Clark http://www.csupomona.edu/~jcclark/ Mockingbird Font Works http://www.mockfont.com/
