Hi Craig,
I don't think I can help much, only to make a few observations.
I've never seen a 'XI' mark attributed to Canongate, only a 'XI.D' (the 'D' representing 'Deniers', 11 Deniers would be equal to the 'Old Scots Standard'.
Early Canongate pieces were known with an assay wriggle mark, but I think only on items somewhat earlier than your ladles.
I can find no maker JRO or JBO. The only Canongate makers that you could fit with a stretch of the imagination would be James RObertson (1 & 2), John RObertson or John ROger but he would be far to early.
The handles are in the Old English Pattern so in theory should not be earlier than about 1760. Canongate marks are not known after the early 1780's.
The bowls and the lower stem are very similar to those found on toddy ladles with baleen handles of this period.
Not much help, I know, just thoughts. You may be interested in this article that Pat came across a while back:
http://archaeologydataservice.ac.uk/cat ... 37_240.pdf" onclick="window.open(this.href);return false;
Whist I am not suggesting at all that your ladles have any connection with Malta whatsoever, but it is interesting to note that there has been confusion between Canongate and Malta and that they are both known to have used the Denier system.
Regards Trev.
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