Copperah is the name, given by the natives to the kernel of the ripe nut after it has been exposed to the sun on mats, until it has become rancid and dissolved. It has recently been shipped to England in this state for the purpose of converting into oil. The exports of copperah from Ceylon were, in 1842, 115 cwts.; in 1843, 2,194; in 1844, 2,397; and in 1852, 39,174 cwts.
The returned value of the copperah or kernels exported from Ceylon, as entered in the Custom House books, is—
| 1840 | 2,508 |
| 1841 | 1,460 |
| 1842 | 3,022 |
| 1843 | 5,795 |
| 1844 | 6,194 |
| 1845 | 3,282 |
| 1846 | 5,517 |
| 1847 | 6,503 |
| 1848 | 12,639 |
| 1849 | 7,819 |
| 1850 | 4,166 |
| 1851 | 9,678 |
| 1852 | 13,325 |
632 cwts. of poonac (being the refuse or cake, after expressing the oil) were exported from Ceylon in 1842. It is worth there about £10 the ton.
The oil from the nut is obtained for culinary purposes by boiling the fresh pulp, and skimming it as it rises. That for exportation is usually obtained by pressing the copperah in a simple press turned by bullocks. Recently, however, steam power has been applied in Colombo, with great advantage. About 2½ gallons of oil per 100 nuts, are usually obtained. It is requisite that care should be taken not to apply too great and sudden a pressure at once, but by degrees an increasing force, so as not to choke the conducting channels of the oil in the press.
In many of the colonies the oil is expressed by the slow and laborious hand process of grating the pulp.
The quantity shipped from Ceylon was 2,250 tuns, in 1842; 3,985 in 1843; 2,331 in 1844; 1,797 in 1845. The quantity in gallons shipped since, was 101,553 in 1846; 197,850 in 1847; 300,146 in 1848; 867,326 in 1849; 407,960 in 1850; 442,700 in 1851; and 749,028 in 1852.
The duty on importation is of and from British possessions, 7d. and ⅞ths. per cwt.; if the produce of foreign possessions, 1s. 3¾ d, per cwt. In the close of 1852, the price of coco-nut oil in the London market was, for Ceylon, £32, £33, to £33 10s. per ton; Cochin, middling to fine, £34 to £35.
The following return shows the Custom House valuation of the oil shipped from Ceylon for a series of years, and which is of course much below its real value:—
| 1839 | £26,597 |
| 1840 | 32,483 |
| 1841 | 24,052 |
| 1842 | 34,242 |
| 1843 | 43,874 |
| 1844 | 24,067 |
| 1845 | 15,945 |
| 1846 | 7,939 |
| 1847 | 19,142 |
| 1848 | 24,839 |
| 1849 | 34,831 |
| 1850 | 35,035 |
| 1851 | 31,444 |
| 1852 | 58,045 |