A blue pigment or coloring material made from cobalt, historically used in ceramics and glass.
From Italian 'azzurro smaltato' (smalt blue) or directly from 'smalt,' a cobalt-based blue pigment that comes from Italian 'smalto' (enamel). The 'a-' prefix here is actually the Arabic article 'al-' that attached to 'smalt' during trade.
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