Option 1: Horn Silver is another name for the mineral cerargyrite, which is a form of silver chloride, thus it contains silver.

Option 2: German Silver, also known as nickel silver, is a silver-colored alloy of copper, nickel and zinc and does not contain any actual silver. So, this is the correct answer.

Option 3: Ruby Silver refers to two minerals, proustite and pyrargyrite, both contain silver as a component of their chemical structure, so they contain silver.

Option 4: Lunar Caustic is a common name for silver nitrate, therefore contains silver.

So, we can conclude that only German Silver does not contain silver although its name suggests otherwise.