Sasieni pipe dating
53, 56, 120 and LC are all classic '3/4 bents with : prior to 1975 for a period yet undetermined (best guess, the '30s) it appears that at least occasionally a "6" was added to the beginning of a pipes shape identifier to indicate that the pipe was fitted with a saddle bit.
NEWLY REPORTED STAMPS: 1957 Carved Head Root - a "C/H" where the shape number is usually found; 1956 & 1958 (possibly 1968) Root - an "SP" underneath the Circled Group Size/Finish code; 1984 a stacked double bowl (to prevent 'wet' smoking) - an "HPL/28" where the shape number is usually found.
23: early in "since the early 1960's Algerian briar has been largely unavailable to Dunhill" should be mid to late.
The 1966 Dunhill catalogues still advised that all shells were Algerian.
(My apologies, as I was looking over some early notes I realized that I forgot to include this in the book).
16: A 'D' with 'tails' has been found on a pipe with a 1923 date code (since a great number of 1923 date coded pipes have been seen without tails I assume the 'tails' usage was very early in 1923.