24 - 11 11 Date perhaps?

If this is a glaze record fraction mark it's in a format more like the date marks I've seen. It could be 24-11 - 4
 with part of the two digit year obscured?

Tony I think you are right - most of the fraction markings are date references, although confusingly it seems, not quite all. This has led to some unnecessarily fractious debates in the past (excuse the pun).

The one you have here looks like the early date format -perhaps from c. 1943-1944. The later format (c.1944-1947) is the classic fraction style which gave these markings their name. In 99 percent of cases, the number on top will be between 1 and 31 (days of the month); the bottom number will be between 1 and 12 (corresponding to months). For me, this closes the case on what the vast majority of these numbers represent, but there are a few exceptions that doubters can always point to and say "Ah-ha! A glaze recipe number!" And they may be right about a certain number of those. But these markings on their own are a small minority.

Sometimes there will be an additional number offset from the fraction. This may refer to the glaze.

One of the things that has been puzzling me about the marks is that most of them are inscribed into the clay body. I assume this was done pre-firing so if the numbers have anything to do with the glaze there would have needed to be a process to match bisque fired pieces with the glazes that were later applied to match the numbers.

The only piece I have where it is obvious that the numbers are inscribed into the glaze rather than the clay is the triangular ashtray with attached bird - 15/3 with a 3 to the left of the fraction. It looks to me as if there are not enough numbers to represent the range of glaze colours.

This might be another example from the world of Crown Lynnology where my assumption based "knowledge" is later proved wrong.

I fear the further we move away from 1945 the more irretrievably lost to posterity these wee questions become. The hanging number might indicate firing number, kiln number, decorator code et.al...

It is interesting you can see evidence that the number was inscribed though the glaze. I think it is more likely to have been some sort of glaze code. Most of our lot is in banana boxes now so I can't physically revisit this old debate as I might like.

But I do seem to recall there being two or three pieces glazed a similar blue, all with the number 28 off to the side though.

Maybe you could have a trawl though the Portage Trust archive sometime?

I don't know anything about any previous debates on the fraction marks representing dates as I've never come across that idea before.  T&C is there anywhere I can check these ideas out?  
T&C I acknowledge and hugely respect your vast knowledge about pottery in NZ and don't want to appear to undermine your opinions, but I will continue to record the fraction marks and put them into the Gallery and see what the end result tells us.
My eyes see a date on this pot and I see the last digit as a 4 not an 11.  This is not easy is it !!

This Vase has very similar looking date lettering like the same person did it, especially the 4.  it may have been made a week earlier on 18-11-45  

Ev - the great thing about this site is you can crowd source raw data to crunch to test the theory. I wondered years ago about these marks and came to a conclusion, at least about the fraction, which satisfied me. The long form date appears to be 1944-45 (my bad sorry). As far as I could make out from looking at lots of pots over the years, the side number did bare some relationship to the glaze, but confusingly there was always one that would come along that would knock that house of cards over.

My guess (read untested theory) is that all the wet glazes looked similar, were left to dry, upon which the glazer would return to etch these markings into the base. Its pretty hard to get the date wrong, but if all the unfired glazes look similar, perhaps they sometimes forgot which lot were spinach and which were rhubarb?

The little letter you often find could possibly be a decorator or finisher marking for quality control testing purposes? It is interesting that this component of the fraction marking system seems to have survived for many years after the trickle/triple glaze line was terminated, and one can find later vases etc. with letters identical (in my fallible eyes) to some of those on these pots from the 1940s.

Today I checked out Richard Quinn's archive file box at the Portage Museum and was very pleased to see this as one of his aims in an early folder:
"To try to resolve the arguments about the fractional marks if possible, but to at least record the differing views if resolution is not possible."
However that was it as I couldn't find anything else about these fraction marks....

A line in the Handpotted notes may interest you T&C -
"Waite says 'S' on the base of Handpotted = Shufflebottom" and then Richard has added 'No proof'.
There were so many interesting pertinent points in his writings and I have yet to read his two main works 'Scrabbling in the Dirt' and 'On My Holidays .... and fings' all related to his Crown Lynn projects and lets hope that the Fractional marks info is in these.

I can't think of anything I have that has a fraction mark, but watching haselnuss' bulk loading of fraction marks led me to the gallery and then back to this link with the obvious date conclusion.

Besides the marks that present as fractions (dd/mm?) there are other numbers that do appear to be dates, in the dd-mm-yy format. I'd be interested to see how glazes on such dated wares relate to those in fraction format.

Beyond the few vases we have seen so far, including Kat's above, note also t&c's blue kettle:
https://www.newzealandpottery.net/t3275p15-crown-lynn-russell-hobbs-coffee-perk-electric-jugs#11678

To that end, would it be appropriate to include such dated wares in the fractions gallery also?

Hard to read but we think VP 4 11 44



and 8 11 44 on this Army coloured vase with pretty interior.

The same person dated this vase also.. its dated 29-11-45

That one is beautiful Kat
A clear stamp and easy to read date makes it rather exceptional in my book