Although a great area is occupied by crystalline rocks in New Zealand, the Archean age of any portion of the series is not yet satisfactorily established; the lower granites and gneisses may belong to this period.
Africa contains enormous tracts of crystalline gneisses, granites and schists, and some of these are almost certainly of Archean age; but in the present state of our knowledge it is impossible to speak more exactly.
The Mona and Kiticni schists; metamorphosed lava and tuffs, with serpentine and dolomite, probably derived from peridotites; there are also gneissic granites and syenites.
The granites are of many varieties, and also, in all probability, of several different geological periods.
Some of the granites of Cornwall and Limousin readily resolve themselves into a white kaolin or argillaceous matter, from which pottery and porcelain are made.
In the same mountain, or even in the same quarry, granites of very different qualities as to soundness and durability occur.
The granites are generally brittle, and many of them do not bind well, but there are a great many which when used under proper conditions make excellent roads.
Some granites which contain hornblende instead of feldspar are desirable.
South of the plateau, in the state of Oaxaca, low mountain ridges composed of granites and gneisses, supposed to be of Archaean age, begin to appear.
Between the 15th and 17th parallels of latitude, in the state of Chiapas and in the republic of Guatemala, there is a second group of ridges composed of granites and schists with an eastward trend.
Many granites have large rounded or angular crystals of felspar (Shap granite, many Cornish granites), well seen on polished faces.
The sequence of crystallization in the granites is of a normal type, and may be ascertained by observing the perfection with which the different minerals have crystallized and the order in which they enclose one another.
The hornblende of granites is usually pale green in section, the augite and enstatite nearly colourless.
Many granites show pearly scales of white mica; others contain dark green or black hornblende in small prisms.
The Rapakiwi granites of Finland have many round or ovoidal felspar crystals scattered through a granitic matrix.
In the tourmaline granites prisms of black schorl occur either singly or in stellate groups.
The granites pass into gneiss and granulite; the gabbros into flaser gabbro and amphibolite; the slates often contain andalusite or chiastolite, and show transitions to mica schists.
True granites are common rocks, especially among the older strata of the earth's crust.
The aplites, pegmatites, graphic granites and muscovite granites are usually richest in silica, while with increase of biotite and hornblende, augite and enstatite the analyses show the presence of more magnesia, iron and lime.
Spheroidal granites of this sort are found in Sweden, Finland, Ireland, &c.
It is bounded on the north by the granites of the Upper Palatinate; and on the south by Alpine limestone, transition-thonschiefer, and the mica-slates of the Tyrol.
The granites have been extensively quarried at Rubislaw, Peterhead and Kemnay.
The later granites subsequent to the plication of the schists have a wide distribution on the Ben Macdhui and Ben Avon range, and on Lochnagar; they stretch eastwards from Ballater by Tarland to Aberdeen and north to Bennachie.
Under the drift lie layers of stratified rock, and under these are the granites and other fire-formed rocks, the beginning of those rock masses which form the solid bulk of the globe.
Granites differ in colouring because the minerals that compose them, the feldspars, quartzes, micas, and hornblendes, have each so wide a range of colour.
So gradually the Huttonian explanation of the origin of granites and other "igneous" rocks, whether massed or in veins, came to be accepted.
The brunt of the controversy settled about the unstratified rocks--granites and their allies--which the Plutonists claimed as of igneous origin.
The granites of Queensland vary very much in their crystalline texture, passing from true granites into porphyry and quartz porphyry.
There are some intrusive granites on Grassy river which are of fine texture and beautiful red colour, which would make very fine monumental stone trimmings for buildings, etc.
The granitesare occasionally cut by pegmatitic dikes.
Truthfully speaking marbles are of lime formation, while granites and jaspers and many others are not.
What is further said of marbles and how are granites imitated?
The material of the houses and defences are rough stones, the granites and sandstones of the hills, cemented, like the ancient Galla cities, with clay.
As a rule they do not proceed directly from the granite, but form separate dikes which may be later than, and consequently may cut, the granites and diorites.
The granito-dioritic-lamprophyres (the first of these two groups) are found in many districts where granites and diorites occur, e.
This indicates a genetic affinity like that which exists between the granitesand the minettes, &c.
In other districts where granites are abundant no rocks of this class are known.
The rounded forms result from the granites flaking off in curved laminæ, like onion-coats.
The sandy and stony maritime region, the foot-hills of the Gháts, granites and traps with large veins and outcrops of quartz; and Wadys lined with thick beds of conglomerate.
The partial ascent of the mighty Shárr gave an admirable study of the mode in which the granites have been enfolded and enveloped by the later eruptions of trap.
Here as elsewhere, the granites run parallel with and seaward of the traps.
The interior decoration is remarkable for the beautiful variety of colors secured by a careful mingling of English, Scotch, and Irish granites grouped as double stems in the balustrade of a spiral stairway.
These granites show in their exterior no sign of pressure structure.
From Mount Betty there are several specimens of white granite, with dark and light mica; it has a great resemblance to the white granites from Sogn, the Dovre district, and Nordland, in Norway.
These porphyries are pierced by greenstone two or three feet thick, and the granites are intersected by numerous veins of amphibolite (hornblende) and greenstone, generally running from east to west.
The granites of the Gallura, as we have already mentioned, were known to the ancients, and highly appreciated in Italy for their beauty and colours.
The granites on the west, as well as the south, of the island include some beds of gneiss and schistes at their extremities.
One would not expect this colour either, which, nevertheless, is that of all the sands and all the granites of Egypt and Arabia.
Slowly the sun descends; and behind us the granites of the town-mummy seem to burn more and more.
Farther on, when we have left behind this region of tombs, the granites alone litter the expanse of sand, granites to which the usury of centuries has given the form of huge round beasts.
And the pyramid seemed to be illumined by some sad dawn of the end of the world, a dawn which made ruddy only the sands and the granites of earth, and left the heavens, pricked with their myriad stars, more awful in their darkness.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "granites" in a variety of sentences. We hope that you will now be able to make sentences using this word.