  Texture specific quark mass matrices which are hermitian and hierarchical are
examined in detail . In the case of texture 6 zeros matrices, out of sixteen
possibilities examined by us, none is able to fit the low energy data (LED),
for example, $V_{us} = 0.2196 \pm 0.0023$, $V_{cb} = 0.0395 \pm 0.0017$,
$\frac{V_{ub}}{V_{cb}} = 0.08 \pm 0.02$, $V_{td}$ lies in the range $0.004 -
0.013$ (PDG). Similarly none of the 32 texture 5 zeros mass matrices considered
is able to reproduce LED. In particular, the latest data from LEP regarding
$|V_{ub}|/|V_{cb}|(=0.093\pm0.016)$ rules out all of them. In the texture 4
zeros case, we find that there is a unique texture structure for $U$ and $D$
mass matrices which is able to fit the data.
