Harry Pristis
Posts: 495
Joined: 7/24/2003 From: Northcentral Florida Status: offline
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Hello, "Green" . . . Welcome! A pontil (note the spelling) is the iron rod which was affixed to the bottom of a bottle while the lip was finished after the bottle was removed from the blow-pipe. A pontil scar is the rough area on the bottom of the bottle left behind when the pontil rod was broken away. The pontil scar is a rough place on the bottom which will abrade your fingernail, if not cut your finger. In an earlier post, a clever, knowledgable, and good-looking list-member had this to say: To produce a "sand pontil scar" (remember "pontil" is the iron rod), the pontil rod tip is tipped with molten glass, then dipped lightly into crushed glass, sand, or crushed furnace slag. The crushed material preserves a boundary between the pontil rod glass and the glass bottle, making it easier to later separate them when the bottle is finished. The appearance of a "sand pontil scar" is that of a peppering of the bottle base with bits of crushed glass or whatever was used. Sometimes this peppering is very light, hard to discern without dragging a fingernail across the bottom surface. Sometimes it is much more prominent. If crushed furnace slag is used as the "boundary material" (notably in black glass bottles), glassgall (sodium sulphate, Na2SO4) may be transferred from the slag to the base of the bottle. This glassgall leaves a milky or turquoise discoloration around the area of the pontil scar. The iron pontil is just that. It is a bare iron rod with a mushroomed tip which is heated, then applied directly to the bottom of the still-molten bottle. Neither graphite nor crushed glass was used as a "boundary material." Because nothing but the bare iron rod was needed, it was dubbed an "improved pontil." The tip of the iron pontil rod, when broken free, left a thin layer of iron adhering to the bottle base. This iron residue is dark gray, but may oxidize to a rust-color (because it is rust!). There is no such thing as a "graphite pontil" scar. Graphite was not used as a "boundary material" or separating agent on the end of a pontil rod. The grey iron residue left by an iron pontil rod may resemble it, but it is not graphite. This is a misconception which persists because people keep using the term. The mistake is found in collector books and on amateur web-sites. The error is thus perpetuated. The term "graphite pontil [scar]" will not go away soon because it has infiltrated the jargon of collectors. New collectors may wish to opt for accuracy by developing the habit of using the term "iron pontil scar" or "improved pontil scar" when they are speaking carefully, that is, for publication. ------------Harry Pristis An "open" pontil scar, so-named because it is "open" in the center or tubular:
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