A Dictionary of Greek and Roman Antiquities/Abaculus
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Abaculus [edit]
ABAC´ULUS (ἀβακίσκος), diminutive of abacus denoted a tile of marble, glass, or any other substance used for making ornamental pavements. They were of various colours (Plin. H. N. xxxvi. § 199; Moschion, ap. Ath. v. 207 d.) [Musivum opus]