Setting aside the potential ambiguity regarding whether silver armor refers to the visual color or the material of the armor, I view "Silver" primarily as a descriptor of metallic texture and rendering characteristics—specifically high contrast and sharp highlights—rather than a specific, inherent hue.
Under the current tagging practices, I don't see much difference between the searching result of silver_armor and grey_armor. Scientifically speaking, except for metals with distinct tinting like gold or copper, most well polished unoxidized metals look identical in terms of their base color. Trying to draw a clear line between "Silver metallic" and "Iron/Steel metallic" based on visual color alone seems practically impossible and highly subjective.
Maybe a more logical classification approach is to use a two-tier system: first distinguish between "metallic/glossy" and "non-metallic/matte" textures, and then differentiate by color. Under this system, the current "silver" category would be break down into [metallic + grey] (for standard polished metal armor) and [metallic + white] (for those ultra-bright, chrome-like paladin or elven-style armor).