I think you might want to do a little digging in your undergrad science books:

The units of electrical conductivity are measured in siemens per meter (S/m). Here’s the electrical conductivity of a few metals:

Stainless Steel: 1.0 - 1.5 × 10^6 S/m
Aluminum: 3.77 × 10^7 S/m
Copper: 5.96 × 10^7 S/m
Gold: 4.52 × 10^7 S/m
Silver: 6.30 × 10^7 S/m

In this list silver has the highest conductivity, and stainless steel the lowest conductivity.