The Basic Principles Of Crystal
对这类水晶晶簇观赏石的欣赏与评价,主要是强调晶体的完整、品种的名贵(如紫水晶、烟晶、发晶等)、造型奇特、含有名贵晶体(如辰砂、辉锑矿等)伴生等。晶簇产于矿床晶洞中,长相完美的并不多见,要完整无损地采集下来,又比较困难,故而采集起来代价较大,精品晶簇价值也就昂贵了。按照透明度指标,水晶越透明,价格越高,好的透明的水晶加工出的成品晶莹剔透、光辉耀眼。透明度高的水晶能提升颜色的艳丽,否则显得呆板无灵性。光学水晶要求全透明、无双晶、无杂质。工艺水晶要求透明、少裂、少瑕疵。熔炼水晶要求透明,可有较多裂纹。三者价值依次降低,熔炼水晶只能作为熔炼水晶玻璃的原料。在工艺水晶中,晶体较大的,可用来做水晶眼镜和雕刻高档工艺品,因而价格较高。
晶及其石英岩类玉石是中低档宝玉石,虽比不上钻石、红蓝宝石的高贵,但在加工中如果构思巧妙而且加工精细,同样具有很高的价值。如中国传统的玛瑙“虾盘”、“龙盘”、“水漫金山�?水胆玛瑙摆件)都被誉为国家级宝玉石。
第一种是“全包裹体”,在水晶结晶的时候把这些物质包裹在晶体里面,这类包裹体所形成的各种景象,大多保持了水晶结晶时的原状,也就是说保存了几亿年的原状,极少受到自然环境的影响。
根据美国已经了解的情况,统计局的专家和其他人口统计学家在他们的视野中提供了一个不可抗拒的水晶球。
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⑦、镀彩:运用类似电镀的手法在水晶表面以不同的色彩,层面较薄,经摩擦可划伤�?;出现划痕,由于镀彩经常位于底部,因此在镀彩底部经常采用其它对象附着,如生肖文镇。
损伤是指水晶由于加工或不小心摔掉、碰撞等原因,人为造成的损坏。它可以是破口,也可以是凹坑等。
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[ C/U ] transparent glass of top of the range, generally with its floor Slice into designs that mirror light
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You will find only some diverse unit-mobile styles, so a number of crystals share a single device-cell type. A very important attribute of the unit mobile is the volume of atoms it has. The overall quantity of atoms in the complete crystal will be the variety in Each individual mobile multiplied by the quantity of unit cells. Copper and aluminum (Al) Each and every have a single atom for each unit cell, while zinc (Zn) and sodium chloride have two. Most crystals have only a few atoms for each device mobile, but there are a few exceptions. Crystals of polymers, for instance, have thousands of atoms in Each individual device cell.
水玉:中国最古老的称法叫水玉,意谓似水之玉,又说是 �?千年之冰所�?�?。唐代诗人温庭筠《题李处士幽居》写道:�?水玉簪头白角巾,瑶琴寂历拂轻�?”。水玉一词最早频繁出于《山海经》:�?又东三百里,日堂庭之�?…�?多水�?”;�?丹山出焉,东南流注于洛水,其中多水玉 ”;�?逐水出焉,北流注于渭,其中多水玉 ”。司马相如《上林赋》曰�?�?水玉磊河 �?。水晶得名水玉,古人是看�?�?其莹如水,其坚如�?�?的质地。
Binary crystals are located in several structures. Some pairs of components sort more than one construction. At room temperature, cadmium sulfide may crystallize possibly within the zinc blende or wurtzite composition. Alumina also has two probable structures at room temperature, α-alumina (corundum) and β-alumina. Other binary crystals show diverse constructions at distinctive temperatures. Among the many website most complicated crystals are All those of silicon dioxide (SiO2), which has seven diverse structures at different temperatures and pressures; the most common of those buildings is quartz.