Graining and Marbling / A Series of Practical Treatises on Material, Tools and Appliances Used; General Operations; Preparing Oil Graining Colors; Mixing; Rubbing; Applying Distemper Colors; Wiping Out; Penciling; The Use of Crayons; Review of Woods; The Graining of Oak, Ash, Cherry, Satinwood, Mahogany, Maple, Bird's Eye Maple, Sycamore, Walnut, Etc.; Marbling in All Shades.

by F. Maire

ONYXES.

163. Onyxes differ from those stones which are known as marbles chiefly in that they are more transparent. The clumps or blotches of variously colored component parts of the conglomerate are much more diversified than can usually be seen in marbles and according to the angle at which they are cut present an endless variation. Sometimes whole slabs show the conglomeration cut across; again in others considerable blank space is found in close proximity and again serpentine waves of veins looking very transparent run around the clumps, etc. Nothing but a close study of the natural stone can give one a perfect idea of their vagaries of form. The general directions given in paragraphs 140 to 149 cover all that could be said here as to the manner of imitating them and the student who has carefully followed the descriptions which are specially given under each marble will find no great difficulty in imitating the variously colored onyxes.

GRANITES, PORPHYRIES AND JASPERS.

164. All the above are closely related and may be bracketed together in describing their imitation. According to their predominating colors they are known as red, gray, white, etc., and have usually the name of the countries from which they come given them in addition.

The ground color should consist of the leading or predominating color, and the rest of the spots are put in by sprinkling or striking the brush against a stick. When the colors have commenced to set, but before they have dried and while still partly wet, turpentine should be sparingly sprinkled upon the work, which will cause the spots to spread and run into each other, but it must not be overdone or a mess will be the result. A little fine flaked mica may be sprinkled upon the work after it is finished, also before drying has been completed; this will give more naturalness to the granite imitations; the porphyry and jasper do not need it.

QUESTIONS ON LESSON XXXI.

159. Describe the character of serpentine marble?

160. How is verd antique marble imitated?

161. How are white-veined black marble and black-veined white marble imitated?

162. What is said of other varieties of marbles?