Dan-
It's too bad your consultant didn't have these references:
 
In Gerald DeBolt's "Dictionary of American Pottery Marks" (1994, Collector
Books, Paducah KY), he states:
"By the late 1920s most American whiteware companies had a product they
marked IVORY, often given a special name such as ROYAL IVORY, ANTIQUE
IVORY, or PRINCESS IVORY.  Since many companies were dating their marks in
the 1920s, the date for a mark can be verified...Since many companies
failed in 1929 or soon thereafter, the IVORY mark was often a death
knell...For companies that survived the Great Depression, IVORY marks
survived well into the 1930s...Some of these companies continued to use
IVORY marks at least to the 1950s" (Debolt 1994:200).     DeBolt's book
includes 200 pages of marks & dates, an 18-page discussion of all known
company mark-dating systems, and a reprint of W. Percival Jervis' 1897
"Book of Pottery Marks".    Every lab should have a copy.
 
Joanne Jasper's "Collectors Encyclopedia of Homer Laughlin China" (1993,
Collector Books, Paducah KY) discusses several patterns that were produced
with this ivory decoration starting in the early 1920s.   She describes it
as:  "...a light yellow body over which an ivory glaze was applied....It is
somewhat amusing to read advertisements from the time...in which HLC touted
the fact that they had broken away from the 'dead white' body of earlier
designs.  HLC was originally founded on the ability of Mr. Homer Laughlin
to produce that same 'dead white' china in contrast to the yellowish
products of other potters in the area" (Jasper 1993:34).    Jasper's book
is worth checking out if you work much with early-20th century American
ceramics.  Lots of dates, old catalog pages, and color photos, including a
side-by-side shot of 2 plates that are identical in every respect except 1
is white and 1 is ivory.
 
Also, a quick perusal of the Gates & Ormerond's 1982 East Liverpool Ohio
guide should turn up several IVORY marks dated to the 1920s & 1930s.
 
Hasta la vista-
Jack Eastman
 
----------
> From: Daniel Warren <[log in to unmask]>
> To:
> Subject: Ivory-glazed Whitewares
> Date: Wednesday, April 01, 1998 1:49 PM
>
> During a recent examination of some gray literature for information on
early
> 20th century sites, I came across a brief unreferenced statement that
> ivory-glazed whitewares are the best diagnostic marker of the
1920s-1930s.  I
> have been unable to any references to this type of whiteware that would
> validate the statement.
>
> Does anyone on the list have experience dealing with this type of
whiteware or
> know of any references that discuss it?
>