أَوْ بِمَعْنَى «مِنْ»، نَحْوُ: «خَاتَمُ فِضَّةٍ».
Translation: Or it may convey the sense of min, as in “a silver ring.”
خَاتَمُ is mudāf; فِضَّةٍ is genitive mudāf ilayh.
The implied min indicates material: the ring is made of silver.
Added example: بَابُ خَشَبٍ, “a wooden door.” The relation can be paraphrased with min, but no actual min occurs in the original construct.