There are examples where Museum Wax has stained porous objects. Because stoneware is a high-fired ceramic, regardless of whether it has a glaze, it is non-porous. If you are still concerned about using Museum Wax, some institutions have applied reversible adhesives to temporarily secure their objects. There was a recent article in the October 2021 issue of Studies in Conservation on this topic.
Velagapudi et al. (2021). Finding a Temporary Adhesive for Securing Objects for Display in Earthquake-Prone Regions. Studies in Conservation. 1-7.
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Nichole Doub
Head Conservator
Maryland Archaeological Conservation Laboratory
Saint Leonard MD
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