Abstract
We have observed a tunneling structure for systems of the type Ag-barrier-metal particles-barrier-Ag, which shows gap structure and multiple-conductance peaks as a function of voltage which closely resembles the point-contact tunneling characteristics reported for the high-Tc superconductors. These data suggest that the appearance of multiple conductance peaks is not due to an intrinsic multiplicity of gaps in the high-Tc superconductors but to charging effects related to the granularity of the material.