Here is a curious word that Dr Jotson uses to describe Sholmes’ pipe in “The Mystery of the Mince-Pie”. As I am not a smoker, I decided to look the word up to find its exact meaning. In fact, the word has no special meaning or tongue-in-cheek use. It truly describes the pipe.

Meershaum – a mineral, hydrous magnesium silicate, occurring in white, claylike masses, used especially for pipe bowls

Usage: “Between his thin lips was a large meershaum pipe.” (from The Complete Casebook of Herlock Sholmes)