  Scanning tunneling spectroscopy on gold layers over-coating \textit{c}-axis
$YBa_2Ca_3O_{7-\delta}$ (YBCO) films reveals proximity induced gap structures.
The gap size reduced exponentially with distance from \textit{a}-axis facets,
indicating that the proximity effect is primarily due to the (100) YBCO facets.
The penetration depth of superconductivity into the gold is $\sim 30$ nm, in
good agreement with estimations for the dirty limit. The extrapolated gap at
the interface is $\sim 15$ meV, consistent with recent point-contact
experiments. The proximity-induced order parameter appears to have predominant
\textit{s}-wave symmetry.
