  Considering massless $u$ and $d$ quarks, and massive (150 MeV) $s$ quarks in
a bag with the bag pressure constant $B^{1/4} = 145$ MeV, a colour-singlet
grand canonical partition function is constructed for temperatures $T = 1-30$
MeV. Then the stability of finite size strangelets is studied minimizing the
free energy as a function of the radius of the bag. The colour-singlet
restriction has several profound effects when compared to colour unprojected
case: (1) Now bulk energy per baryon is increased by about $250$ MeV making the
strange quark matter unbound. (2) The shell structures are more pronounced
(deeper). (3) Positions of the shell closure are shifted to lower $A$-values,
the first deepest one occuring at $A=2$, famous $H$-particle ! (4) The shell
structure at $A=2$ vanishes only at $T\sim 30$ MeV, though for higher
$A$-values it happens so at $T\sim 20$ MeV.
