Here's why:

* Metallic Bonding: This type of bonding occurs between metal atoms. In metals, the outer electrons are loosely held and can move freely throughout the structure. This creates a "sea" of electrons that hold the positively charged metal ions together.

* Silver and Copper: Both silver and copper are metals. Therefore, when they are combined (like in an alloy), they form a metallic bond.

Important Note: Silver and copper can also form intermetallic compounds, which have specific chemical formulas and often exhibit unique properties. These compounds are still held together by metallic bonding.