Ornamental stones

Azurite Hydrous copper carbonate Blue 3.8 3.8 Crystalline Ornamental stone, gemstone, blue pigment, building stone, making lime... 

Rhodonite has been occasionally used for an ornamental stone, Its name is derived from the Greek meaning a rose, because of the color,... 

The materials most commonly used as gems and ornamental stones are listed in Table 2.9. This is by no means a complete listing of all materials ever used in jewelry or for decorative purposes. There are many worked specimens that are one-of-a-kind, made from unexpected materials that were opportunistically obtained. These often pose problems of identification and consequently of conservation, since once a stone has been worked it loses its natural luster and form. Stones have been altered with dyes and heat for thousands of years, so it does not hold true that just because something is in an old artifact or Grandma s necklace that it cannot be dyed or otherwise not natural. Synthetics are relatively new, but imitations are as old as the stones themselves. If someone wanted a red gem, and there were no rubies available, then a garnet or spinel could be used instead. No emeralds Use an olivine (peridot) or green sapphire. A synthetic must have the same composition and internal structure as the natural material, but an imitation just has to look like the natural stone. 

Alabaster is a form of gypsum (hydrated calcium sulfate q.v), occurring as a fine-grained, massive mineral which is used as an ornamental stone. It can become coloured, a property dependent on associated minerals - for example, hematite q.v.) will impart a red colour. Oriental alabaster is a term for a stalagmitic variety of calcite q.v) characterised by well-marked banding it should therefore not be confused with alabaster proper. 

Lapis lazuli, or simply lapis, is a rock composed of a mixture of minerals, usually calcite, pyrite and lazurite (qq.v.), with the latter being the dominant constituent. Occurrence is as a blue rock containing brassy yellow crystals (pyrite) with white streaks due to calcite. It is formed from the metamorphism of limestones by an alkaline igneous intrusion (Deer et al., 1992 Rutley, 1988). Other silicate minerals such as hatiyne, sodalite, diopside, forsterite, muscovite and wollastonite (. v.) may also be present. The term is often used incorrectly to refer to the mineral lazurite, which is only one of its components. Lapis lazuli is most famously known from the deposit in the Kokcha River valley, Afghanistan, where it has been mined for more than 6000 years for use in jewellery, as an ornamental stone and as a pigment, ft is also known from Mt Vesuvius (Italy), Colorado and California (USA), Siberia and Chile. 

Amber. The hardest of all the resins, amber is stiU collected along the shores of the Baltic Sea. The pieces are poHshed to an attractive pale yeUow-to-dark brown stone and made into ornamental objects. 

Cold-hammering was used in the late Stone Age to produce plates of gold for ornamental purposes, and this metal has always been synonymous with beauty, wealth and power. Considerable quantities were accumulated by ancient peoples. The coffin of Tutankhamun (a minor Pharaoh who was only 18 when he died) contained no less than 112 kg of gold, and the legendary Aztec and Inca hoards in Mexico and Peru were a major reason for the Spanish conquests of Central and South America in the early sixteenth century. Today, the greatest hoard of gold is the 30000 tonnes of bullion (i.e. bars) lying in the vaults of the US Federal Reserve Bank... 

Schmuck, m. ornament jewelry finery, schmiicken, v.t. adorn, decorate, dress, Schmuck-stein, m. gem, gem stone, -waren, f.pl. jewelry, jewels,... 

FIGURE 15.15 The blue stones in this ancient Egyptian ornament are lapis lazuli. This semiprecious stone is an aluminosilicate colored by S2 and S, impurities. The blue color is due to S3 and the h i nt of green to S2. ... 

Pruning of pome fruit crops will lead to DFR levels comparable to those for stone fruit crops therefore, a common database for both crop groups (for tree fruits) should be compiled. Further generic sets may be developed for fruit vegetables, grapes, and ornamentals. 

Throughout the final phases, the solar wind will sweep across the Earth, tearing up the surface. The atoms of our dead will be driven from below and returned to the Sun. The Earth will surrender her dead. Finally, lit up by the bright white glare of the central star, the ejected matter will blossom into a beautiful planetary nebula rather like the one that so delightfully ornaments the constellation of the Lyre. The atoms of all human beings will shine in the sky, mixed with those of the animals and the stones. 

Quartzite. Quartzite is a very compact, exceptionally hard and tough meta-morphic rock derived from sandstone. It consists mainly of rather large crystals of quartz (composed of silicon dioxide) naturally cemented by secondary quartz. Most varieties of quartzite contain over 90% quartz, and in some cases the quartz content exceeds 95% of the total weight of the stone. The color of most quartzite is white or light yellow, but if it contains iron oxide impurities it is red, while other metal oxide impurities may cause the rock to display patchy color variations. Quartzite is very hard, which makes it difficult to quarry. Nevertheless, because of its strength and resistance to weathering, it has occasionally been used for construchon, sculphng statuary, and ornamentation. 

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