I think Frogpatch and I were typing at the same time !! It is not unusual not to be able to find many patterns !! These were usually done in limited numbers !! Would have been extremely boring for an artist to sit and do the same thing over and over !! If they got the blanks as greenware it would have been easy to scratch in the name before firing !! It would have been a little unusual because greenware is delicate before it is fired at least once !! If I am not mistaken some Limoges was actually made here but don`t know if that would be the case for yours !! It would sure help if we could see it and the mark !!
And so you will understand about value and this applies to many things,,value is only determined by what someone is willing to pay !! It makes no difference if you have the only one that was ever made,,unless someone other than you wants it too and is willing to pay more for it,,it value is still whatever you paid for it !! Old and rare does not equal value !! Supply and demand does !!
Hope this helps !!