This section is from the book "Notes On Building Construction", by Henry Fidler. Also available from Amazon: Notes on building construction.
The calcined limestone is divided, according to its action in slaking and setting, into the following classes: -
2. Poor Limes.
3. Hydraulic Limes.
4. Cements .Natural. Artificial.
These classes merge gradually the one into the other, without sharp distinctions, the difference between them depending upon the nature and amount of the foreign constituents associated with the lime, and upon the degree of calcination to which the stone has been subjected.
The physical characteristics of the raw stone are no index to the properties of the lime or cement produced from it. These properties may however be inferred from the nature and proportions of the chemical constituents of the stone. A general composition has been assigned to the materials yielding each of the classes above mentioned, but it must be borne in mind that this is only an approximate indication of quality, and that the behaviour when calcined and treated with 'water is the only safe means of classification.
The following Table shows the composition of a number of limestones and cement stones, chosen as characteristic examples, and intended to give some idea of the varieties actually met with.
In comparing these analyses with others, it must be borne in mind that these show the composition of the raw stone, or raw material from which the lime or cement is produced. Analysis of the burnt lime or cement would in each case have given a higher percentage of clay and sand, and the lime and magnesia would not appear as carbonates. (The carbonic acid would have been expelled during calcination.)
1 Magnesium carbonate.
Composition of Raw Stone or Raw Material. | |||||
Cement produced. | Description. | Carbonate of Lime and Carbonate of Magnesia. | Clay, Sand, Iron, etc. | Water and Loss. | Analyst or Authority. |
Rich or Fat Limes. | Carrara Marble (see p. 55) | 100 carb. lime | •• | .. | Vicat. |
White Chalk . | 98.6 carb. lime .4 carb. magnesia 99.0 | 2 iron, manganese and phosphates •8 silica and alumina 1.0 | .. | Schweitzer (Reid). | |
Bath Oolite (see p. 59) | 94.5 carb. lime 2.5 carb. magnesia 97.0 | l.2 iron and alumina 1.2 | 1.8 | Professors Daniel and Wheatstone; Commission on Stone for Houses of Parliament. | |
Portland Oolite (see p. 60) | 95.2 carb. lime 1.2 carb. magnesia 96.4 | •5 iron and alumina 1.2 silica 1.7 | 1.9 | Do. | |
Poor Limes. | Siliciferous Oolite, Chilmark Stone (see p. 63) | 79.0 carb. lime 3.7 carb. magnesia 82.7 | 2.0 iron and alumina 10.4 silica (nearly all sand) 12.4 | 4.2 | Do. |
Feebly Hydiaulic. | Grey Chalk, Hailing (see p. 155) | 92 carb. lime . | 8 clay . | .. | Col. Scott, R.E. |
Hydraulic. | Roach Abbey, Dolomite (see p. 59) | 57.5 carb. lime 39.4 carb. magnesia 96.9 | .7 iron and alumina .8 silica 1.5 | 1.6 | Professors Daniel and Wheatstone; Commission on Stone for Houses of Parliament. |
Bolsover, Dolomite (see p. 59) | 51.1 carb. lime 40.2 carb. magnesia 91.3 | 1.8 iron and alumina 3.6 silica 5.4 | 3 3 | Do. | |
Carboniferous, Aberthaw (see p. 155) | 86.2 carb. lime | 11.2 clay . | 2.6 | Phillips (Captain Smiths Vicat). | |
Grey Chalk, Sussex (see p. 155) | 83 carb. lime . | 17 clay | .. | Col. Scott, R.B. |
Composition of Raw Stone or Raw Material.1 | ||||||
Nature of Lime or Cement produced. | Description. | Carbonate of Lime and Carbonate of Magnesia. | Clay, Sand, Iron, etc. | Water and Loss. | Analyst or Authority. | |
Eminently Hydraulic. | Blue Lias, Lyme Regis (see p. 155) | 79.2 carb. lime | 17.3 silica and alumina | 3.5 | Reid. | Some varieties contain less clay. |
Carboniferous, Holywell, Wales (Halkin Mountain Limestone), see p. 155 | 71 .55 carb. lime 1.35 carb. magnesia 72.90 | 3.5 alumina 2.2 iron. .8 alkalies 20.l silica 26-6 | .5 | Muspratt. | Average about 12.5 per cent. | |
Arden, near Glasgow (see p. 155) | 68.0 carb. lime •8 carb. magnesia 68.8 | 25.8 clay 2.4 iron •6 chlorides 25.8 | 2.4 | Ingram. | ||
Slow Setting Cements. 1 | ' Heavy English Portland 3 White Chalk and 1 Clay dried, but unburnt (see p. 160) | 77. carb. lime 77.0 | 2.7 alumina 3.5 iron 15.8 silica 1.0 alkalies 23.0 .... | .. | Reid. | |
Portland Cement, good | 58 to 63 carb. lime | 21 to 24 silica 5 to 9 alumina 3 to 6 oxide iron 0.5 to 1.5 sulphuric acid | .. | Specification of 1'Administration desPontetCliaussees. | Currie & Co.'s circular | |
Kimmeridge Clay (Boulogne) (Natural Portland) unbumt | 76.6 carb. lime •8 carb. magnesia 77.4 | 9.2 iron and alumina 13.4 silica 22.6 | .. | Gilmore. | ||
Native Magnesia (Madras) | 99 carb. magnesia. | .5 silic | •5 | Dr. Malcomson (Captain Smith's Vicat.) | ||
Moderately Quick Cements. | Dolomite, Portgyfu, North Wales | 21.4 carb. lime 61.15 carb. magnesia 82.55 | 5.58 silica 2.07 alumina 8.76 iron 16-41 | 1.1 | Professor Cabutt (Lipowitz). | |
Rosendale Cement Stone, Layer No. 9. High Falls, Ulster, New York | 43.3 carb. lime 26.0 carb. magnesia 69.3 | 207 silica and alumina 1*9 iron 2.0 sulphuric acid 4.2 alkaline chlorides 28.8 25.69 iron and alumina. 1.50 sulphuric acid | 1.9 | Professor Boyntou (Gilmore). | ||
Medina Cement Stone (see p. 158) | 47.80 carb. lime 47.80 | 24.50 silica 51.69 | •51 | Ingram. |
1 For analyses of the burnt Portland cement see p. 227.
Composition of Raw Stone ok Raw Material.1 | ||||||
Nature of Lime or Cement produced | Description. | Carbonate of Lime and Carbonate of Magnesia. | Clay, Sand, Iron, etc. | Water and Loss. | Analyst or Authority. | |
Quick Cements. | Roman Cement Stone from Calderwood (Scotland), see p. 159 | 54.0 carb. lime 14.2 carb. magnesia 68.2 | 3.4 alumina 13.31 iron 8.8 silica 2.6 phosphates 28.1 | 37 | Professor Penny (Gilmore). | |
Medina Cement Stone from Portsmouth, Isle of Wight (see p. 15S) | 45.32 carb. lime •50 carb. magnesia 45.82 | 14.15 iron and alumina 1.70 sulphuric acid 37.65 silica 53 50 | .68 | |||
Roman Cement Stone from Boulogne Septaria | 61.6 carb. lime 61.6 | 4 8 alumina 15.0 silica 9.0 iron 28.8 | 9.6 | Dropping (Captain Smiths Vicat). | ||
Roman Cement Stone from Sheppy Septaria | 6.57 carb. lime •5 carb. magnesia 66.2 | 6.6 alumina 6.8 iron 1.9 manganese 18.0 silica 32 5 | 1.30 | Co. | ||
Rosendale Cement Stone, Layer No. 16, High Falls, New York | 46.0 carb. lime 17.8 carb. magnesia 63.8 | 30.0 silica and alumina 1.3 iron. •2 sulphuric acid 4.l alkaline chlorides 35.6 | .7 | Professor Boynton (Gilmore). |
A few rough, tests may be applied to a limestone to see if it is likely to furnish a hydraulic lime or cement.
Such a stone will generally have an earthy texture, and will weather to a brown surface.
Acid will not cause upon it so great an effervescence as upon purer limestones.
When breathed upon or moistened a clayey odour is emitted from the stone.
The best plan, however, is to burn a little of the stone in a small experimental kiln, to judge by the slaking, and by the behaviour of pats made from the paste.
1 For analyses of the burnt Roman cement see p. 241.
 
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