Reticulation is sometimes referred to as the black art of metalsmithing and is an organic process using the heat of a dual gas torch. No 2 pieces turn out alike. Reticulation silver is an alloy of 80% silver and 20% copper, but because of the process of reticulating the silver, the pure silver is drawn to the surface. Once reticulated, this alloy is highly tarnish resistant.
Please read our blog on Reticulation HERE When done correctly a texture similar to this picture can be produced.