This jar was originally in Phil Robinson's musuem.  Where Phil obtained it, I'm not sure.  I have heard of one other.  It's definitely one of my favorites.  It is unmarked, as so many of the very early jars were, and is hand blown, something extremely rare in the world of jars.

It takes a version of the famous "Willoughby Stopple" (well, famous if you're a jar collector anyway) which is quite different and much rarer than the normal cast iron stopple.

All Willoughby stopples are essentially two plates of metal with a piece of rubber between them and a thumbscrew to press the two plates together, compressing the rubber between them.  The rubber has nowhere to go but to squeeze out from the two plates agains the neck of the jar forming the seal.  It's hard for me to believe that this seal worked well, but it was fairly popular during the civil war era and earlier so it must have worked to some degree or another.

The more common variety is designed to fit into the neck of a jar and rest on a ledge there.  Consequently the top and bottom are the same size so they can both fit into the neck above the ledge.

The rarer type shown here is designed to sit on top of the jar while allowing the bottom plate and the rubber between to the two plates to fit into the neck of the jar.  Consequently, the top plate was bigger and rested on the lip of the jar and the smaller plate hung down into the neck of the jar.

This jar is a lovely shade of blue.  I have a hard time classifying it as "cobalt", "sapphire" or "cornflower".  It's a bit softer than those - more like a "pastel" blue.

This jar held a high place of honor in Phil's musuem and now that he's passed away, I'm very happy that I have something like this from his musuem.  I have no idea how many collectors have looked at this jar over the years, but considering Phil's willingness to take anybody through, I'd bet it's one of my "most viewed jars".