New to me 1911 Calabash - asbestos a possiblity? Any other info appreciated

[delta]

Calabash
If I'm interpreting the hallmarks correctly (WH - anchor, lion, M) it was made in Birmingham, England in 1911 by William Harrison. What I'm confused about - is he the silversmith or the pipe maker or both? I'm curious who made it/sold it originally. If anyone knows anything else about this pipe specifically or this style in general it would be greatly appreciated.
More importantly, in my recent research I've discovered that these pipes were sometimes made with asbestos bowls?!? That would be an interesting fact to know, as I've already smoked this one several times. It doesn't look like the asbestos bowls I saw googling around, seems harder than meerschaum, hopefully plaster. If it is, how safe is THAT to smoke? It'd be a shame if I had to set this on a shelf, it smokes wonderfully.
One unusual feature (at least it seemed to me) is that the bowl is 1.5" at the top, tapering evenly 1.75" to the bottom. I could fit a lot of tobacco in there if I ever filled it up. Are large bowls like this common for pipes of this style and era? You'd think the shape would make it difficult to smoke, but I've had no problems.
Another is the .5" metal screen I assume is meant to sit in the bowl. It works, but is not attached or press fitted in any way, it easily falls out or shifts if I tip the pipe. Is it possible this isn't original to the pipe?

 

[pitchfork]

It looks like meerschaum to me. All of the asbestos pipes I've seen were black. Calabash bowls vary in size -- some were made with narrow gourds and therefore have fairly narrow bowls.
As for the metal grate/screen -- I have no idea if it's original or not, but they show up from time to time in pipes of that era.

 

[delta]

Thanks for the info. It seems pretty hard to be meerschaum (I can't mark it with a thumbnail) but I'm not familiar with old meerschaum. I've looked for pictures of known plaster bowls to compare with this one, but no luck.

 

[fishnbanjo]

Any chance it's porcelain? Many Calabash pipes had porcelain bowls. Regards.

banjo

 

[delta]

Any chance it's porcelain? Many Calabash pipes had porcelain bowls. Regards.

banjo

I don't think so, unless they weren't glazed or all of the glazing has worn off.

 

[jonasclark]

I suspect this bowl is meerschaum. Yes, I, too, have seen asbestos bowls, and they've all been glossy gray or black (and were all the fit-in type one usually thinks of as a calabash bowl). The only in-set bowls I've seen on these have been meerschaum, porcelain, or plaster. Those little screens were often put in the bottom of meerschaums to help them color; buttons or even coins with holes drilled in them were sometimes substituted. Calling Condorlover-- where are you? Condorlover knows all about those button screens.
Beautiful pipe you've got. Super big bowl. Enjoy the heck out of it!