Powdered smalt.

An impure oxide of cobalt, obtained by roasting cobalt-ore, and used in the preparation of smalt and as a blue colouring-matter (cobalt blue) for…

= A. 3b.

A deep blue colour like that of smalt.

ultramarine blue (or colour). A blue colour like that of this pigment.

(a) n. a deep vivid blue; (b) adj. of this colour.

The rich blue colour of smalt. Cf. powder blue, n. 2a.

a small Eurasian butterfly, Cyaniris semiargus (family Lycaenidae), now extinct in Britain, the male of which is a dull purplish blue.

= lazulite, n.; cf. blue spar n.

Hydrous phosphate of aluminium and magnesium, found in blue monoclinic crystals; also, the colour of this mineral. ¶Sometimes used = lapis lazuli, n.

The blue pigment, also called cobalt-blue n. prepared from this mineral, largely used in staining glass. Also the deep blue colour of this.

In the names of pigments used in painting, decorative arts, etc. the blue pigment cobalt blue.

a turquoise or cobalt blue.

The ultramarine blue of Sèvres porcelain; also called bleu de Sèvres. Also attributive.

The vivid deep blue colour of certain gentian flowers (see gentian, n. 1a). Cf. gentian, n. 3.

The vivid deep blue colour of certain gentian flowers. Cf. gentian blue, n.

A rich deep blue; mazarine blue. Now rare.

A very deep blue colour; the colour of the night sky.

A complex silicate containing sulphur, of bright blue colour, used as a pigment (see ultramarine, adj. n.). Also, the colour of this mineral.

(a) n. a type of laundry whitener, now chiefly used as a brightening agent (cf. blue, n. 1c); (also) the clear cobalt blue colour of this…

Short for royal blue n. adj. at compounds 1.

A rich blue colour applied to porcelain or stoneware.

= delphinium, n. b.

A deep blue like that of the indigo-blue delphinium.

a shade of deep blue.