French term
émailler
DOC: 1907 Museum catalog of ancient Egyptian mirrors. Catalog entry.
CONTEXT: 44102. Moule gabarit pour manche de miroir ou écrin de miroir. - Bois. -- [....] New paragraph: Cette tablette a pu servir de creux à mouler, moitié par moitié, des manches de miroirs en matière plastique, en fritte sableuse ou terre ***à émailler***; elle a pu également servir de matrice à battre les placages d'or ou d'argent. Les godets à paroi évasée jouaient-ils, en pareil cas, un rôle analogue et complémentaire? Il est à remarquer que leurs deux diamètres ne correspondent ni au diamètre du collier, ni à celui de la partie la plus renflée du bulbe, ni à celui du manche en question. Peut-être servaient-ils à broyer ou à malaxer les poudres colorantes dont se composait **l'émail**. Des traces de bleu y adhèrent encore. Le vide de la partie supérieure de la tablette, qui paraît intentionnel, devait, en pareil cas, servir à supporter le disque dans l'opération de l'emmanchement.
Ignore the 44012 on the plate, sic for 44102.
https://books.google.com/books?id=qhs2AQAAMAAJ last plate # XXV
ATTEMPT: This tablet could have been used for hollow casting mirror handles made of plastic material, of sandy frit, or clay ***for the enameling to be enameled/covered with enamel***, one half at a time;
ISSUE: I'm not sure what "terre à emailler" means here, the one thing I don't think it is is enameled clay (en terre émaillée). And I think it connects to "l'émail" further down. I also found that:
Egyptian faïence, a sandy frit covered with a white, blue, or green enamel.
The Egyptian method of enamelling frits composed of siliceous sand.
Enamel powder could be produced in two ways, either by powdering coloured glass, or by mixing colourless glass powder with pigments such as a metallic oxide.
Thanks in advance for any clarification.
When entering new questions, KudoZ askers are given an opportunity* to classify the difficulty of their questions as 'easy' or 'pro'. If you feel a question marked 'easy' should actually be marked 'pro', and if you have earned more than 20 KudoZ points, you can click the "Vote PRO" button to recommend that change.
How to tell the difference between "easy" and "pro" questions:
An easy question is one that any bilingual person would be able to answer correctly. (Or in the case of monolingual questions, an easy question is one that any native speaker of the language would be able to answer correctly.)
A pro question is anything else... in other words, any question that requires knowledge or skills that are specialized (even slightly).
Another way to think of the difficulty levels is this: an easy question is one that deals with everyday conversation. A pro question is anything else.
When deciding between easy and pro, err on the side of pro. Most questions will be pro.
* Note: non-member askers are not given the option of entering 'pro' questions; the only way for their questions to be classified as 'pro' is for a ProZ.com member or members to re-classify it.
Discussion
Note the usage in FR of infinitive where we will sometime use a passive infinitive, e.g. 'à vendre' > 'to be sold'.
I feel sure that the sense here is 'clay that would subsequently have to be enamelled', rather than the 'frit, which presumably fused to produce a shiny result in its own right, without needing to be glazed; do also be ware that in some cases, an 'émail' like this can be a 'glaze' — though the description you've found is certainly describing a classic enamel.
Note that 'terre' is one sort of clay, as in 'terracotta' and 'earthenware' — as distinct from 'argile'.