11. Earthenware and Porcelain Kelim

[11]. The poskim are divided about the status of porcelain. Radbaz (Responsa Radbaz 3:401) wrote that it is proper to be stringent and consider it earthenware, as it is hard to know whether the coating is impervious. He even conducted an experiment: he cooked in a porcelain kli and found that its weight increased a bit, implying that it absorbed matter. Many showed concern for his view, including: Pri Ḥadash 451:26; Maḥzik Berakha 451:10; MB 451:163; Ben Ish Ḥai, Tzav 14; R. Ḥayim Palachi in Mo’ed Le-kol Ḥai 4:3; and Kol Mevasser 1:80. Against them, many practiced leniency and considered it to be like glass. Several poskim ruled accordingly, including Shiyarei Knesset Ha-gedola OḤ 451; Hagahot Beit Yosef 30 (though he was personally stringent, he did not agree to this stringency for others); and She’elat Ya’avetz 1:67. Rav Goren ruled accordingly for the IDF with regard to porcelain plates that have no cracks and that are generally used with a kli sheni (Meshiv Milḥama 2:150).

It seems that the primary reasoning of those who adopt the stringent view is concern that the glass coating is imperfect. It emerges from Pri Ḥadash and Ḥida (Maḥazik Berakha) that if the porcelain is real, there are grounds for leniency, but it is often counterfeited. Indeed, in the past, many would coat the earthenware with a glasslike substance with a paintbrush, and sometimes the coating was imperfect and had cracks. However, when the earthenware is immersed in liquid glass, the coating is uniform, smooth, and strong. Therefore, although le-khatḥila one should show concern for the stringent view, when necessary, one may be lenient, since nowadays the manufacture of porcelain is high quality, i.e., the glass coating is strong and the kli does not absorb. However, when the kli has cracks, its status reverts to being like earthenware.

Today there are high-quality plates made (by Arcopal and others) from sand. Their texture is hard like glass, and, as can be seen when they break, the interior material is hard and impervious, like glass. Although their surfaces are made rough for aesthetic reasons, they have the status of glassware and are kashered by means of hagala, as will be explained in the next section.