attractive piece Robert, and regret I'm unable to provide an attribution.
If you have Gulliver you'll know that Stuart, T/Webb, S. & W., H.G. Richardson and Hodgetts Richardson, all made pieces with threading, and I've just seen another maker I was unaware of - Daniel Pearce.......... all within the period you mention. Possibly there were other makers in addition to these.
Looking at a side profile of your jug, the threading appears reasonably proud - it doesn't strike me as unusually flat or sunk when compared to some of Gulliver's examples - but you're certainly lucky if this has avoided all damage. As you say, most pieces with this decoration show some loss of thread.
You don't mention size, so difficult to assess use, but this pronounced 'helmet' design to the top rim is often indicative of creamers, provided they aren't 12" tall - Gulliver plays safe, and appears to describe all such containers simply as either large or small jugs.
The hollow handle appears very unusual - despite showing a wide variety of handle designs, to the best of my knowledge all of those shown in Gulliver are solid. Regret I can't comment of the crack, other than to say that it's not that uncommon to find them where bodies meet handles, although perhaps more often on pre 1860 ish pieces with top down handles rather than your type which I'd understood provided improvement in joint strength.
You don't mention wear - just guessing, but might the absence of this indicate perhaps a later piece, or not of the period you mention?
Sorry none of this helps.
