Another technique practiced in the middle of the 19th century involved heating the pontil rod until it was hot enough to fuse to the bottle’s base. The primary advantage of this bare-iron technique was that it saved time and labor, eliminating the need to gather and form the piece of glass at the end of the pontil rod. Indications that a bare-iron pontil rod was used include a rusty residue on the base of the bottle. Sometimes this mark is disc shaped, other times it shows up as a ring.

For glassblowers who were working without assistants, the blowpipe was often pressed into service as a pontil rod. This technique required a great deal of skill because the glassbower would have to work very quickly to set the bottle down so it laid flat, crack off the blowpipe, quickly gather more molten glass at its end, and then re-attach the blowpipe to the base of the bottle. If the glassblower took too long to accomplish these steps, the bottle could cool too much, which could cause it to crack. For this reason, some glassblowers probably just had assistants bring them a nearby blowpipe that was used instead of a pontil rod.

One interesting variation on the glass-tipped pontil was the sand pontil, in which the molten glass at the end of the pontil rod was rolled in sand just before being attached to the bottle’s base. This allowed the pontil glass to adhere to the base, while the sand acted as a kind of perforation, making it easier to remove the bottle from the pontil rod. Scars left by sand pontils are generally wider than those left by glass-tipped or bare-iron ones.

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