My experience or observation is that if the dagger has plated crossguards or an aluminum or pot metal eagle then the scabbard has plated metal fittings and no scabbard weight.

The most variable part was the eagle. They came in small boxes of about 100 and manufacturers probably bough a bunch at at a time. I have seen entire boxes of early ones at shows. Late ones of aluminum too. In a word, some manufacturers had supplies left at the end of war. Probabably the smaller guys.

Crossguards are next but lasted for a much shorter time probably because they were bulkyer and more expensive. You occasionally see them on transitional daggers. Also early SS RZM daggers such as 121/34, some M7/29, etc.

The one constant seems to be the rune button.

Dave