A classification is given of what may turn out to be all separable nuc
lear simple C-algebras of real rank zero and stable rank one. (These
terms refer to density of the invertible elements in the sets of self-
adjoint elements and all elements, respectively, after adjunction of a
unit.) The C-algebras considered are those that can be expressed as
the inductive limit of a sequence of finite direct sums of homogeneous
C-algebras with spectrum 3-dimensional finite CW complexes. This cla
ssification is also extended to include certain nonsimple algebras. Th
e invariant used is the abelian group K- = K-0 + K-1, together with t
he distinguished subset arising from partial unitaries in the algebra,
the graded dimension range. With the semigroup generated by the grade
d dimension range as positive cone, K- is an ordered group with the R
iesz decomposition property which, in a suitable sense (allowing torsi
on) is unperforated. In fact, K- is an arbitrary (countable) graded o
rdered group with these two properties. (This extends the theorem of E
ffros, Handelman, and Shen.)