I’ve now reweighed all of his semisses of RRC 14 and 18 and all the triens of 18 a total of 60 specimens. Three were gross outlier and I’ve excluded them. The first two were early yesterday and thus I suspect might be user error (i.e. me getting used the handwriting and scales etc…). The other was the last coin of today not in Haeberlin’s printed volume but with his handwritten weight on the specimen.
Of the 57 remaining weights the average difference from reweighing is .11%, BUT for a full half of the readings the difference falls between .07% and .1%. We might also note that in 50 of the 57 cases Haeberlin’s weight is slightly lower than the new weight. This trend in the data suggests that there is a simple very slight calibration error either of his scale or mine.
Long and the short of it is that I think we should trust his weights and I’m not sure it is worth my time to keep up my systematic reweighing.
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Other thoughts. The Semisses of RRC 18 are more consistent in quality and character than those of RRC 14. Case in point, all of Haeberlin’s RRC 18/2 specimens have 12 o’clock design alignment, but while his RRC 14/2 has a a tendency towards 12 it is not stable at all:
The RRC 18/3s appear even more uniform in manufacture and fabric.
Another suggestive data trend is the difference in the number of spues for RRC 14/2 and RRC 18/2.
Of 16 specimens of RRC 14/2, 12 have only one spue, whereas just 4 have two.
Of the 19 specimens of RRC 18/2, 15 have two spues, where as just 5 have one.
I take this to be evidence of experimentation in the manufacture process to refine techniques, but I see no difference in the number of voids at least in quantification terms. I’d want to put the two trays out in front of me together, perhaps impossible, to eye ball if the quality of the casting seems different.
I also notice looking at all the RRC 18 semisses together a two different diameters. Most fall in the 48-50 mm range, but three are much bigger up at 55-58 mm. The wider ones also seem thinner. I want to keep an eye on this.
Liv Mariah Yarrow 