Most bottles made in the United States before the 1850s, when the snap case tool virtually replaced the pontil rod (also called the punte or punty), have a pontil mark on their bases.The mark is formed when a bottle is transferred from the blowpipe to the pontil rod, which, unlike the blowpipe, is solid.Using a blowpipe for empontilling was likely done to both save on the number of tools used by the glass blower and to save time.
This is circumstantial proof that one blowpipe was usually used for both blowing and empontilling.
Image #2 shows a very large and distinct blowpipe pontil on the base of a “Jenny Lind calabash” bottle that dates from about 1850. Sand pontil scar (image #3) – The sand pontil scar was also a common method of empontilling a bottle to hold it for finishing, though less common on American made bottles than the other three primary methods described here.
The noted image shows a sand pontil with the distortion (indented slightly) made by the pontil ball tip in evidence. Iron or” improved” pontil scar (image #4) – This fascinating type of pontil mark is also referred to as simply an “iron pontil” or “improved pontil.” It is also commonly referred to as a “graphite pontil.” This is erroneous as there is no graphite (carbon) associated with any improved or iron pontil mark.
Apparently the term originated from the fact that the substance often looks like a graphite smear.
A glass tipped pontil rod made contact with most – or all – of the bottle base within the confines of the diameter of the pontil rod tip.