Knot rings do not necessarily note naval. Many stirrup shaped knuckle guards (five ball or not) have the enlarged casting boss near the pommel without having being drilled for a ring. The long grooves on a grip are regarded as reeding, as opposed to ribbing (at least in many texts.
A small spadroon file with some variety that I have archived You'll see another shallow reeded ivory in there, files to large to easily attach but lots to browse.
https://drive.google.com/drive/folde...DQ?usp=sharing
The shallow reeding/ribbing of the object sword is less common than a more regular spacing while not being terribly unusual. Although not necessarily the origin, I have noted it on some grips (typically dove head hilts) from the Netherlands. However, Ames of the US using an uneven reeding well into the 19th century, albeit more contoured vs the smooth with grooves we see on the object sword. A couple of my ebony grips below and I could show a handful of my horns but not really relevant to the object sword.
British horn grips quite brown are steamed and pressed. Continental carved and polished black until later ranging from greenish to dark brown.
Some of my stuff.
Cheers
GC