Those water stains used that have been already mentioned, and all others, are prepared in the same manner as for wood, but they are afterwards strained or filtered. They are employed warm or only tepid, too great heat in the stain, as also too large a proportion of acid in the cleansing fluid, very injuriously affecting the surface of the ivory. Increasing the temperature in many cases also considerably deepens, and in others, entirely changes the colours sought; the most certain results arise when the stains are used at about 100° Fahr., they then act with sufficient rapidity, and the ivory may be removed from time to time for examination and replaced until the required tint is obtained. Average times of immersion are mentioned for the above temperature, but some pieces of ivory are found to acquire the colour more rapidly than others; when sufficiently stained the ivory is again well rinsed in water, and when one stain has to be followed by another, the ivory is also always first well rinsed before it is transferred to the second bath of colour. Having been finally allowed to thoroughly dry, the work is re-polished by friction, first with a few drops of oil on soft clean rag to give it a lustre, the friction being then continued with dry clean rag, until the oil disappears.

A pale yellow results from an immersion of about one minute in the tepid stain given by 60 grains of saffron, boiled for some hours in half a pint of water. Five to fifteen minutes produces bright and deep canary yellows, but all these colours are rather fugitive. A stain made from four ounces of fustic dust and chips boiled in one quart of water, produces very similar, but darker and far more permanent results. Ivory subjected to either of the above stains for about fifteen minutes, washed, and then placed for from one to three minutes in the brazil water stain, previously mentioned, acquires an orange; and the same, then treated with nitro-muriate of tin, yields a clearer orange of a brighter, redder tone. The action of the nitro-muriate of tin upon the stained ivory is always exceedingly rapid: the fluid may be plentifully applied to the work with the brush, but immersion is safer, as producing more equal effects. The work in either case, being immediately transferred to a clean water bath to check further change, so soon as the required colour appears.

Fine scarlet cloth is employed for dyeing various tones of red, the finely divided dye extracted from the cloth, being found to yield more uniform colours than stains prepared from the crude cochineal. With a stain prepared from a piece of cloth about a foot square cut into shreds, and boiled with the addition of about ten grains of pearlash in half a pint of water for five or six hours; immersion for from three to ten minutes, gives a clear, delicate pink of different depths of colour. Ivory placed in this stain for one hour, and subsequently for half an an hour in the alum mordant mentioned for wood, obtains a pink of a bright crimson character. Pink colours of a different and dull full tone, may be obtained by immersion for three minutes in the brazil water stain, followed by treatment with nitro-muriate of tin; and when the brazil is used for six minutes, a still deeper colour results.

A crimson red follows when the ivory is allowed to remain for from two to three hours in the tepid red cloth stain. The addition of a small quantity of sulphuric acid, in the proportion of about one part of acid to sixty of the stain, gives a very brilliant crimson of a rather scarlet tinge, employed for billiard balls. The plain red cloth stain applied for about an hour, and the ivory then treated for about half an hour in the pearl-ash solution, affords bright purple colours, and when the iron solution replaces the pearlash, more sombre purples. The addition of further quantities of alkali to the cloth stain, in place of the acid, yields purple reds of varying depth of colour.

Ivory immersed for fifteen minutes in the decoction of brazil, and then treated with the nitro-muriate of tin and immediately washed, acquires a duller and rather deeper red than that given by the first red cloth stain; and the depth of colour may be considerably increased by a longer immersion, or by a higher temperature in the brazil bath. A dull scarlet or brick red is obtained when the brazil bath is followed by immersion for from thirty to sixty minutes, in the alum mordant for wood. Fifteen minutes in the brazil, and then three to four minutes in the solution of pearlash previously mentioned, gives full red purples deepening to maroon.

Ivory immersed for five minutes in the logwood water stain given for wood, obtains a good warm brown, and continued in the stain for about half an hour, a deep chocolate brown; tones between, again arising from varying the length of exposure. Immersion in the logwood for ten minutes, washing, and then dipping for one or two seconds in the pearlash solution and again instantly washing, gives a deep red brown, and a similar treatment for one minute in that of alum, a deep purple brown.

Blue stains may be obtained from the ordinary, fluid sulphate of indigo of commerce, in the proportion of half a drachm to one pint of previously boiled water, with the addition of about 10 grains of carbonate of potash. One to two minutes immersion, and immediately washing, yields a delicate turquoise, five minutes, a bright full blue, and ten to fifteen minutes, a considerable depth of colour. The blues are rather fugitive, so that in practice the ivory has to be stained to a deeper shade than permanently required. Nitro-muriate of tin entirely destroys the colour.

Staining with saffron or fustic for five minutes, and then for the same period in the indigo, as above, produces a clear pea green, and when the latter stain is continued for ten minutes, a deep grass green; the greens from fustic being more permanent and of a yellower shade. The sequence in which the two stains are employed also considerably influences the tone of colour, the character of which is determined by the second; being bluer when the indigo is used after either yellow stain, and yellower, when the saffron or fustic follow the indigo. Nitro-muriate of tin brightens the colours of those greens in which the fustic is employed last, but it requires to be used rapidly and with caution, to prevent its attacking the indigo. Immersion in the blue stain first, and for fifteen minutes, followed by the fustic for thirty, stains the ivory a deep bright green of the colour formerly largely employed for table knife handles; a colour which may otherwise be obtained, by a very protracted immersion of the ivory, extending over some weeks, in a clear solution of verdigris in dilute vinegar and water.

Jet black is obtained by immersing the ivory in the logwood stain for fifteen minutes, well washing, and then placing it for five minutes, in the solution of one ounce of sulphate of iron in one quart of water, employed for staining wood.