We have already shown the limits within which the different ingredients of clay vary. In the following tables we have collected a certain number of analyses of the best-known clays. These analyses have usually been made with pure clays which in most cases have been cleaned.

They do not show, therefore, the impurities which may be contained in clays, and hence have more interest for the savant than for the manufacturer.

We must also not forget that they can only serve as a rough guide, since the composition of clays varies from one place to another, even in a distance of a few metres. Hence, whenever a manufacturer wishes for information as to the chemical composition of his clays he should take, with every precaution, a sample from each bed, the physical appearance of which seems different from the others.

Locality.

Hydroscopic Water.

Composition of Clays when dried at 110o C.

Physical

Properties and

Applications.

Water in Com- hi nation.

Silica.

Aluminium.

Oxide of Iron.

Lime.

Mag-nesium.

Alkalies.

I. Refractory Clays.

A. Kaolins.

France -

Brittany

I3.00

48.OO

36.00

...

2.00

Limousin

• • •

13.00

48.OO

37.OO

...

• •

...

2.50

Nievre .

• •

I2.6o

49.OO

36.00

...

• • .

...

I.60

Pyrenees

• •

11.50

48.OO

34.60

traces.

0.84

...

2.15

England -

Cornwall

...

13.00

48.35

36.00

0.75

...

..

O.96

Germany -

Dolau (near Halle)

• •

12.76

48.15

37.03

O.60

O.27

O.30

O.82

Russia .

• •

12.60

48.OO

36.00

. • .

• • •

...

2.4O

China .

..

11.20

50.00

33.70

• • •

..

...

I.90

B. Various Clays.

Germany -

Eifel

3.50

13.00

46.60

39.30

...

...

...

...

Refractory.

Grossalmerode (Duchy of Hesse)

0.43

I4.OO

47.50

34.37

I.24

O.50

1.00

...

Grey and plastic, below the ligneous earths, very pure. - Mixed with quartz sand, is used for Hessian crucibles, which bear sudden changes of temperature without cracking.

Lautersheim

(Prussia) .

...

I3.56

49.00

33.00

2.IO

2.00

0.20

White and plastic - Fine pottery of Meit-lach and Satregue-mines.

Loshhayn (near Meissen, Saxe) .

2.70

II.70

61.52

20.92

O.50

traces.

4.971

Blackish, mixed with quartz. - Saggers (Meissen Manufactory).

England -

Devon .

...

11.20

49.60

37.40

...

...

...

...

Grey, plastic, base of English flint-ware.

Stourbridge .

* a a

17.34

45.25

28.77

7.72

0.47

...

...

Black, not very plastic, comes from coalfield, infusible. - Crucibles for melting steel, and refractory bricks.

Austria -

Gottweith (near Krems)

1.00

10.00

65.60

20.75

2.00

1.55

traces.

...

Dirty green with red spots. - Saggers (Vienna Manufac-tory).

Theuberg( Bohemia)

0.49

IO.OO

58.39

27.74

races.

0.74

1.00

..

Plastic, grey, below the lignite clays. taggers (Elbogen Manufactory).

Belgium -

Andcnne . .

• •

I9.OO

52.00

27.00

2.00

• •

.. • •

• . •

White plastic. - Glassware pots, crucibles, faicfices.

Angleur

8.30

I4.30

46.30

39.50

...

..

...

Refractory.

!

Hygroscopic Water.

Composition of Clays when dried at 110° C.

Physical

Properties and

Applications.

Locality.

Water in Combination.

Silica.

Alumi- niutn.

Oxide of Iron.

Lime.

Magnesium.

Alkalies.

Antragues

...

9.OO

7I.OO

19.OO

Grey and plastic. - Glass-ware pots, gas retorts, refractory bricks.

Denmark -

|

Isle of Bornholm .

O.27

5.92

72.50

19.50

I.OO

O.50

O.50

þ • •

Plastic, grey, superior to chalk. - China saggars (Copenhagen Manufactory).

France -

Abondant (near Dreux, Eurc-et-Loir).

...

13.10

50.60

35.20

O.40

...

...

...

White, plastic, very refractory. - Crucibles for melting steel, china saggers.

Belin (Ardennes) .

• •

1.27

63.57

27.45

O.I5

0.55

• •

traces.

Plastic, grey, infusible. - Faiences (Douai).

Boulogne (Pas-de-Calais)

2.24

6.28

69.42

18.OO

0.95

2.00

3.27

Hard, greyish brown, infusible. - Fine faiences and pottery.

Breteuil (Eure)

I2.50

14.30

48.30

35.60

...

• • •

þ • •

• þ

Refractory. - Bricks and refractory pieces.

Dourdan (Setne-et-Oise)...

þ •

9.20

60.60

26.39

2.50

O.84

• þ þ

• • •

Plastic, infusible.

Echassieres (Allier)

• • •

16.40

49.20

34.OO

• • •

þ þ «

• • •

• •

Plastic, white. - Hard porcelains.

Etrepigney (Jura) .

...

9.96

70.00

18.50

O.50

O.75

traces.

• a •

Rich, greenish grains of quartz, infusible. - Faiences (Doubs).

Forges - les - Eaux (Seine-Inferieure)

...

II.OO

65.OO

24.OO

traces.

þ þ •

• • þ

Plastic, grey. - Stoneware articles, glassware pots, refractory products, fine faiences, common faiences.

Gaujacq (Landes) .

O.42

14.50

46.50

38. IO

traces.

...

Plastic and white. - China saggers (Ville-dieu).

Hayange (Moselle)

• • •

7.50

66.10

[9.80

6.3O

...

...

...

Yellow, sandy. - Refractory bricks.

Huelgoat (Finistere)

5.IO

I4.30

47.90

38.OO

þ • a

...

...

Refractory.

Klingenberg(Vosges]

...

16.OO

48.32

32.48

1.52

I.64

...

...

Plastic, grey. - Glassware pots, glass pots.

Labouchade (Allier)

...

I2.00

55.40

26.40

4.20

...

...

• • •

Hard, yellowish white. - Glass-ware pots.

La Malaise (Hatite-Vienne)

1.55

15.OO

52.55

26.50

O.55

3.00

I.50

þ * •

Plastic, with red veins, infusible. - China saggers (Limoges Manufactory).

Laumede (Dor-dogne)

4.00

13.60

48.70

36.50

• þ •

• • •

Refractory.

Leyval (Charante-Infcrieure).

• þ •

I2.00

52.00

3I.60

4.4O

• •

White, marbled with red. - Glass-ware pots.

Miglos (Ariege)

6.50

14.00

46.30

36.70

...

• * þ

..

þ þ þ

Refractory.

Locality

Hydroscopic Water.

Composition of Clays when dried at 110o C.

Physical

Properties and

Applications.

Water in Combination.

Silica.

Aluminium.

Oxide of Iron.

Lime.

Magnesium.

Alkalies.

Montereau (Yonne)

IO.OO

64.4O

24.60

traces.

..

• •

Plastic, light grey, very variable in composition. - Used for English faience clay.

Proving (Seine-et-Marne)

O.30

57.OO

37.OO

4.OO

I.70

þ • •

• •

Plastic, whitish. - Refractory bricks china saggers.

Retourneloup (Seine -et-Marne)

2.27

16.96

42.OO

38.96

O.85

I.04

O.I7

...

Plastic, grey, with red veins. - Sevres saggers.

Salavas (Ardeche) .

1.45

II.05

58.76

25.10

2.50

2.51

..

Plastic, rose-coloured, turning grey in the | kilns. - Crucibles for smelting steel.

Savignics (Oise)

...

þ þ •

65.OO

3I.OO

2.00

traces.

2.00

...

Plastic, black, above chalk. - Native pottery.

Russia -

Gloukoff

2.71

16.50

46.35

37.OO

...

• • *

O.15

White, plastic. - Base of St. Petersburg china.

Valendar

O.52

6.75

65.27

24.19

I.OO

...

, 2.02

Plastic, greyish.

II. POTTERY CLAYS.

England -

Longport..

IO.60

54.50

16.5O

3.13

3.37

þ • •

, Plastic, violet coloured. - Staffordshire bricks.

France -

|

Arcueil (Seine)

II.OI

62.I4

22 OO

3.09

1.68

traces

• •

Plastic, black, below coarse limestone. - Paris pottery.

Livernon (Lot)

...

18.OO

49.00

24.OO

6.26

2.00

...

Red. - Pottery, imi-tation of Ktruscan pottery.

Yaugirard (Seine) .

14.58

51.84

26.10

4.91

2.25

0.23

...

Plastic, blackish, vein-ed. - Paris pottery.

III. Marly Clays.

France -

Grandpre

• •

13.13

58.50

I3.50

8.33

5.19

1.35

Tiles and pottery.

Saint - Henri (near Marseilles).

...

2I.70

38.00

24.OO

4.50

11.00

0.80

...

Tiles and pottery.

IV. Lehm (Vegetable Monla).

Nordlingen .

...

11.55

;i66.o;

I2.90

5.27

' 2.6c

1.61

...

Reddish and sandy. - Uricks.