Chapter XI: The Commercial Nomenclature of the Earth Colours

Mention has already been made of the great confusion prevailing in the nomenclature of pigments, and that many of these are put on the market under a variety of names taken from different languages.

Although the number of the earth colours is far smaller than that of the artificial colouring matters, the nomenclature is in a no less confused condition.

Most frequently, earth colours are named after the localities where they are either discovered or prepared, in combination with the word indicating the colour of the product--for example: Cologne white, Vienna white--or the term “earth” (Verona earth, Veronese green, etc.). Whilst these names give, to some extent, an indication of the nature of the pigment, others have no reference to it at all; such as colcothar, bole, umber, etc. Finally, a number of other names in use are calculated to produce the impression that the earth colours in question are of an entirely different nature to their real one. As an example, we may cite the name “French chalk,” which is not a chalk at all, but consists of the mineral talc. Black chalk, again, is not chalk (calcium carbonate), but a black shale; and graphite is often termed blacklead, although it contains no lead at all, and the name is merely a survival from the time when pencils of metallic lead were used for drawing.

In order to bring some kind of order into the various names which are applied to the earth colours, a list of those in current use is appended. Many of these names, it may be stated, have been selected in a purely arbitrary manner, some manufacturers, for instance, selling ordinary chalk under a variety of foreign names, for the purpose of thereby obtaining higher prices. These borrowed names would seem to be superfluous, to say the least. Pure and properly levigated chalk is the same article everywhere, whether prepared from English, French or German limestone; and in all cases the simple name, “chalk,” with an explanatory “single,” “double,” or “triple” levigated, should be quite sufficient.

In the case of earth colours that are really obtained of special quality in certain localities, such as terra di Siena, green earth from Verona, or the like, the corresponding name might be retained, even if the pigment did not originate from the locality in question, as a generic term for a pigment possessing certain properties and of a certain composition.

In the following classification, the names of the earth colours are given in accordance with their colour and chemical composition.

WHITE EARTH COLOURS

_Carbonate of Lime_:

Chalk; levigated chalk; Vienna white; Spanish white; marble white; artists’ white; Bougival white; Champagne chalk; Paris chalk; Cologne chalk; Mountain chalk; craie; blanc minéral; Blanc de Champagne; Blanc de Meudon; Blanc de Bougival; Blanc de Troyes; Blanc d’Orleans; Blanc de Rouen; Blanc de Briançon.

_Basic Carbonate of Lime_:

Vienna white; Vienna lime; pearl white; whiting; Blanc de chaux; Blanc de Vienne.

_Note._--The calcareous marls, consisting of carbonate of lime and clay, are also frequently sold under the above names, the same being the case with gypsum.

_Silicate of Alumina_:

White earth; pipeclay; Dutch white; Cologne earth; terre d’Argile; Argile blanc; Terre blanche.

_Silicate of Magnesia_ (mineralogically, talc and soapstone):

Talc; Venetian earth; French chalk; Venetian white; glossy white; feather white; shale white; face-powder white; Blanc de Venise; Blanc d’Espagne; Blanc de fard.

_Note._--Fine grades of white lead are also sold as Venetian white, Spanish white and shale white; but can easily be recognised by their weight. The term “prepared” white, frequently applied to earth colours in the trade, usually indicates that the material in question has been either levigated, ground or burnt--in short, put through some kind of preparatory treatment--and is therefore in frequent use for all the colours.

_Barium sulphate_:

Heavy spar; barytes; heavy earth; mineral white.

_Precipitated colours_:

Permanent white; blanc fixe.

YELLOW EARTH COLOURS

_Ferric hydroxide_, with admixtures of ferric oxide, clay, lime, ferric silicate, basic ferric sulphate, etc.

Ochre; iron ochre; golden ochre; satin ochre (satinober); pit ochre; vitriol ochre; Mars yellow; Chinese yellow; Imperial yellow; permanent yellow; terra di Siena; umber; Italian earth; Roman earth; bronze ochre; oxide yellow, etc.

Yellow ochre; Jaune de Mars; Terre d’Italie.

_Ferric Silicate_:

Yellow earth; Argile jaune; yellow wash.

RED EARTH COLOURS

_Ferric oxide_ (with alumina and silica).

Bolus; bole; Terra sigillata; Lemnos earth; red chalk; raddle; Striegau earth.

_Ferric oxide_:

Colcothar; English red; angel red; Pompeii red; Persian red; Indian red; Berlin red; Naples red; Nuremberg red; crocus; chemical red; Crocus Martis iron saffron; caput mortuum; raddle; rouge de fer; Rouge de Perse; Rouge des Indes; Rouge de Mars; Rouge d’Angleterre.

BROWN EARTH COLOURS

_Ferric oxide_:

Ferric hydroxide; Ferric silicate (conf. Yellow Earth Colours, which are often sold under the same names as the browns. The paler kinds are usually called “pale” or “golden,” such as pale ochre, golden ochre, etc.). Terra di Siena; burnt Siena; satinober; mahogany brown; Vandyke brown.

_Ferric silicate, Clay_:

Umber; umber brown; Roman earth; Roman umber; Turkish brown; Sicilian brown; Cyprus earth; chestnut brown; burnt umber; ombre; Terre d’ombre; Ombre brulée.

_Organic decomposition products_:

Cologne umber; Cologne earth; Cassel brown; Spanish brown; mahogany brown; Vandyke brown; brown carmine; Terre brun de Cologne; Brun de Cologne; Brun d’Espagne; Ombre de Cologne; Brun de Cassel; Terre d’Ombre; Cologne brown.

_Asphaltum_ (_mineral rosin_):

Asphaltum brown; bistre; earth brown; bitumen; pitch brown; Asphalte; Brun de bitume; Bitume.

GREEN EARTH COLOURS

_Ferrous oxide with silica, alumina, lime, etc._:

Green earth; Verona green; Celadon green; Verona earth; Italian green; stone green; Bohemian earth; Cyprus earth; Tyrol green; permanent green; green ochre; Terre verte; Terre de Vérone; Vert d’Italie.

_Cupric carbonate_:

Malachite green; mountain green; Hungarian green; copper green; mineral green; Tyrolese green; shale green; Vert de montagne; Vert d’Hongrie.

BLUE EARTH COLOURS

_Cupric carbonate_:

Malachite blue; mountain blue; lazulite blue; azure blue; mineral blue; copper blue; Hamburg blue; English blue; Cendres bleues; Bleu d’azure; Bleu de cuivre; Vert-de-gris bleu; blue verditer.

GREY EARTH COLOURS

_Grey clay shale_:

Mineral grey; silver grey; stone grey; slate grey.

BLACK EARTH COLOURS

_Carbon_:

Graphite; blacklead; plumbago; iron black.

_Clay shale_:

Black chalk; slate black; Spanish black; Spanish chalk; oil black; Schiste noir; Noir d’Espagne.

INDEX

Alabaster. _See_ Gypsum.

Alumina, silicate of, 21, 22

Aluminium-potassium silicate, 21

Alum sludge, 32

----, artificial ochre from, 148

----, ferric oxide pigments from, 164–167

Ammonium salts, artificial ochre from, 145, 146

Anhydrite, 19

Anthracolite, 13

Arragonite, 13

Asphaltum, 37, 38.
_See also_ Bitumen.

----, brown, 174, 175

Augite, 179

Azurite, 33

Ball Mills, 55–56

Barium carbonate, 20

---- sulphate.
_See_ Barytes.

Barytes, 19, 20, 119–122

----, artificial, 133

----, correcting colour of, 121

----, detecting, in white lead, 120

----, low covering power of, 121

Black chalk, 38

---- earth colours, 185–196

---- ----, trade names of, 202

---- earths, 6, 38–39

---- schist, 38

Bitumen, 174, 175

Blanc fixe, 19

Blue earth colours, 183–184

---- ----, trade names of, 202

---- earths, 4, 33–36

Bole, 31, 32, 152–154

Bone breccia, 13

Brown coal, pigments from, 175

---- earth colours, 168–175

---- ----, trade names of, 200

---- earths, 5, 36–38

Calcareous marl, 110, 111

---- tuff, 12

Calcining, 81

---- Ferric oxide, 161–164

---- furnaces.
_See_ Furnaces.

---- lime, 88–90

---- ochre, 132–136

Calcite, 11, 12, 14, 15

Calcium carbonate, 12, 14, 15, 16

---- ----, action of acids on, 15

---- hydroxide, 16

---- sulphate.
_See_ Gypsum.

Calc sinter, 12

---- spar.
_See_ Calcite.

Caledonian brown, 36

Cappagh brown, 36

Caput mortuum. _See_ Colcothar.

Carbon brown, 37

---- in limestone, 16

Cassel brown, 37, 38, 174

Celadon green. _See_ Green earth.

Chalk, 13

----, black, 194–196

----, colour of, 103

----, correcting colour of, 104, 105, 106

----, covering power of, 106

----, grinding, 101

----, impurities in, 103, 104

----, precipitated, 107–109

----, preparation and properties of, 98–106

Classification of earth colours, 4–8

Clay, 21–23

Clay, formation of, 113

----, impurities in, 114–119

---- in ochre, 128

----, levigating, 114–117

Colcothar, 160, 161, 162

Cologne earth, 173, 174

Commercial nomenclature of earth colours, 197–202

Crushers and Breakers, 43–45

Crushing, 77–80

---- machinery, 43–60

Disintegrators, 58–60

Distemper, weatherproof, 94

Dolomite, 18

Draining and Drying, 66–77

Drying appliances, 73–77

Dyestuffs for improving earth colours, 85

Edge runners, 48–55

English red, 160

Ferric hydroxide in ochre, 128–132

---- oxide, artificial ochre from, 143–144

---- ---- as by-product, 30

---- ----, burnt, 158–164

---- ----, calcining, 161–164

---- ---- in lime, detection of, 91

---- ----, native, as pigment, 154

---- ---- pigments from alum sludge, 164–167

---- ----, range of colours, 29

---- ---- shading, 28

---- ----, violet shades from, 164

Ferrous sulphate, artificial ochre from, 139–143, 146–148

Filter-cloths, cleaning, 72

Filter-presses, 70–73

Furnaces, calcining, 158, 162, 163, 166

Granulator, 43

Graphite, 38, 39, 185–194

---- as a lubricant, 194

---- as anticorrosive, 194

Graphite in the manufacture of lead pencils, 191–193

---- for crucibles, 193

----, refining, 189–192

Green earth, 176–180

---- ----, artificial, 180

---- ----, improving, 178

---- ---- colours, 176–184

---- ----, trade names of, 201

---- earths, 5

Grey earth colours, trade names of, 202

Grey earths, 38

Gypsum, 18, 19, 111, 112

Heavy spar. _See_ Barytes.

Hematite, 155

----, brown, 23, 30, 31

----, red, 28, 30

Hydro-extractor, 66–70

Improving earth colours, 84, 85

Indian red, 29, 160

Iron cream, 29

---- glance, 154

---- in limestone, 17

---- ore, bog, 25, 31

---- ----, micaceous, 28

Ironstone, brown, 23, 24, 25

----, clay, 24

----, red, 28–30

Kaolin, 21, 22, 112–119

Lazulite, 183

Lemnos earth. _See_ Bole.

Levigation, 60–65

Lime, absorption of carbon dioxide by, 93

----, action of, on casein, 94

----, ----, on colours, 93, 98

----, calcining, 88–90

----, caustic, preparation of, 87–94

----, double compound of oxide and carbonate, 93

---- from mussel shells, 98

----, impurities in, 91, 92

---- in clay, 22

---- ----, eliminating, 117–119

---- in ochre, 129

Lime in the preparation of artificial ochre, 140–144

----, moulding, 96–98

----, quick, 16

----, slaked, 16

Limestone, 11–18

----, suitability of, for colour-making, 92

Limonite, 25

Magnesia, carbonate of, 123, 124

---- in lime, 91

---- in limestone, 17

Magnesium silicate, 21

Malachite, 35

---- blue, 183

Marble, 11, 14, 15

Minerals, testing for suitability as pigments, 172

Mine sludge, 32

Mixing earth colours, 81–84

Moulding, 85, 86

Mountain chalk, 12

---- milk, 12

Muffle, burning ochre in the, 158–160

Muriacite, 19

Muschelkalk, 13

Ochre, 24, 25, 26

----, blue.
_See_ Vivianite.

----, calcining, 132–136

----, English, 138

----, green, 180

----, pit, 148–150

----, Roman, 137, 138

----, Siena, 137, 138

----, testing, 130–132

----, toning with chalk, 144

----, toning with clay, 144

----, vitriol, 146–148

Ochres, 128–150

----, artificial, 138–146

---- as by-products, 146–150

----, burnt, 158–164

---- from various deposits, 136–138

----, Italian, 137, 138

Oolithic limestone, 13

Organic matter in lime, 91

Pastel crayons, 126

Pearl white, 94

Permanent white, 19, 122

Pipeclay. _See_ Kaolin.

Preparation of colour earths, 40–86

Pulverisers, 56–58

Raddle, 29, 155–158

----, impurities in, 156

----, testing, 157

Raw materials for earth colours, 8–39

Red earth colours, 151–167

---- ----, trade names of, 200

Red earths, 4, 27–33

Sampling raw earths, 9

Selenite, 18

Shading pigments with permanent white, 19

Siena, Terra di, 25, 26, 27, 168–170

----, ----. _See also_ Italian ochre.

Siderosilicate, 171

Sifting, 77–80

Soapstone, 20, 21.
_See_ also Steatite.

Spanish brown, 174

Sprudelstein, 15

Steatite, 20, 21, 125, 126

Stamps, 45–48

Talc, 20, 21, 124, 125

Terra sigillata. _See_ Bole.

Testing purity of raw earths, 10

Trade names of earth colours, 197–202

Ultramarine, 33

Umber, 36, 170–174

----, Cologne, 173, 174

----, true, 170–173

Vandyke Brown, 38, 174

Vermilion, 151

Verona earth. _See_ Green earth.

Vienna white, 95–98

Vivianite, 33, 34, 184

White earth colours, 87–126

White earth, trade names of, 111, 198, 199

White earths, 4

White raw materials and pigmentary earths, 11–23

Witherite, 20

Working earth colour deposits, 9

Yellow earth colours, 127–150

---- ----, trade names of, 100

Yellow earth, 150

Yellow earths, 4, 23–27

PRINTED IN GREAT BRITAIN BY RICHARD CLAY & SONS, LIMITED,
PARIS GARDEN, STAMFORD ST., S.E., AND BUNGAY, SUFFOLK.

The Manufacture of Paint

THE PRACTICAL HANDBOOK FOR PAINT
MANUFACTURERS, MERCHANTS AND PAINTERS

BY

J. CRUICKSHANK SMITH, B.Sc.

Second Edition--Revised and Enlarged

DEMY 8VO. 73 ILLUSTRATIONS. 300 PAGES

CONTENTS

CHAP. PART I

I.--SCOPE OF SUBJECT AND DEFINITION OF TERMS.
II.--STORING AND HANDLING RAW MATERIAL.
III.--TESTING AND VALUATION OF RAW MATERIAL.