That is the mark from 1905 to 1915.
It more than likely doesn't have a name. Well...it would have, but those records are long gone. It might have a Schleiger Number, which means there's no set name, like Princess, and there will be a number attached to the pattern, like Schleigar 335 or Schleiger 115-A.
In the late 1930's and early 1940's, Arlene Schleiger of Omaha, Nebraska was trying to find pieces to fill in her mother's set of china. She couldn't find names, numbers, or any info to figure out what was what. She figured out there was a need to have a common means or method to identify them, so she created one.
She assigned a number to the patterns as she entered them in her book. The term Schleiger Number was started.
It's not complete and by no means, perfect. Some collectors follow it, some don't. Sadly, you'll find the same pattern listed 4 different ways on 4 different sites. Which makes it so much fun for the rest of us.
I'll be honest, the main questions for valuing Haviland are, which Haviland made it, the age, the type of pattern (floral rim, lattice or basket wave, solid color, gold, etc.), the style of the plate (embossed, scalloped, etc.), and if an artist actually signed the designs. That's compared with the current market and what we find in sales and databases.
I can tell you that it's very similar to the Sch. 800 series and a bit like the Trianon pattern. The plate shape looks to be a Theo shape which would fit the period of mark.
I wish I could say the value will be much higher. As for the value, based on my records off all the other 800 series and patterns using the Theo blanks from teh same period, a single dinner plate. $35 to $45
is the average value of similar recorded patterns from the same time frame.
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