You are right - The quality of the materials used and slight differences in the vulcanization process are likely the difference. For instance my Roma stem is on the softer side, and if I don't keep after it it oxidizes quickly. Conversely I've had a couple pipes that used German Vulcanite, and that was a tad harder(although this hardness difference could easily be explained by a coating of carnuba) and never showed oxidation. Even thought the end result is always Vulcanite, the term Ebonite is used instead(by suppliers and artisan pipe makers), probably to distinguish from the more common and lower quality Vulcanite used on a lot of factory pipes.Mr Beardsley wrote: ↑Thu Feb 07, 2019 6:53 pmMore makers need to use Juma for stems. I have one pipe with a juma stem and it's actually my favorite material. Somewhere between vulcanite and ebonite (and yes even though they are technically the same they don't feel the same)houtenziel wrote: ↑Thu Feb 07, 2019 6:41 pmSo far, I've had a Vauen, Rattray, Morgan Bones, and a Lucite Pete that were all pretty much like biting down on glass. I haven't had a Perspex, so that could be one to try for me.
I have read also that there have been attempts at creating treated acrylics that are softer, to get the best of both worlds. "Ashtonite" being one that often has the lore of being a vulcanite/acrylic composite, despite that being a chemical impossibility.
Your mention of Juma also reminds me that I missed Bakelite
