Create a 3D model of a dirty silver necklace with a cross pendant. The chain should be medium-sized, chunky, and made from oxidized silver with a rugged, worn-out look. The metal should have a matte, tarnished finish, subtle scratches, and a distressed texture for a vintage feel. The cross pendant should be bold, simple, and rustic, with either rounded edges or a flat, angular design, matching the dark silver tone of the necklace.