@Bakl346
nah, they aren't THAT heavy. Lorem with her wings and horns still weight less than 100 kg. Aka, horns density is more than flesh, but still probably less than iron or steel, or at the very least same weight as those metals.
And there aren't really any info on how strong those horns are, i actually doubt that they are strong at all. They could be used with demonification, but it's probably impossible to maintain that form when horn torn off from the body.