Yes intresting, the darker ones I had were heavier than than the lighter coloured. My suspician is rhino would be heavier but thats is just a guess so could be tottaly wrong.
They are meant to be fairly stiff, like thick wire filled cable if you bend them them hold the bent position for a while before straightening slowly,have but one I tried to soften a bit with neatsfoot oil, sadley it became very floppy & whippy unlike a real sjambok.
The longest one of yours looks very weaponlike the shorter sturdy ones are typical of herdsman tools.
Tim. Youd have to have some serious tastes to like those, they can cut to the bone, even through clothing!
Spiral