盛稀珍藏艺术品精品推荐 定向球形陨石

盛稀珍藏艺术品精品推荐 定向球形陨石

陨石的一种。也有人称作石铁陨石，这类陨石中硅酸盐与镍铁合金的含量各占50%。定向又分为两个子类：橄榄陨石与中铁陨石。 根据硅酸盐矿物成分特征,将石铁陨石划分为4种:①橄榄陨铁(类型符号P)，主要由橄榄石和组成基质的铁镍金属构成；②中铁陨石(M),主要由斜长石、辉石和铁镍组成;③古铜-鳞英铁陨石(S)，主要由铁镍、古铜辉石和鳞石英组成；④橄榄-古铜铁陨石(Lo),主要由铁镍、橄榄石和古铜辉石构成。橄榄陨铁中铁镍金属的Ni含量约为8～15%,其成分与八面体铁陨石相似,橄榄石的成分为Fa12-22（橄榄石中的铁橄榄石分子的百分数），橄榄陨铁的冷却速率比八面体铁陨石低，认为它可能是来自陨石母体或小行星内部更深处。占陨石数量的2%～4%，铁镍和硅酸盐矿物含量相当(30%～65%)。主要矿物有橄榄石、各种辉石、铁纹石和镍纹石。

A type of meteorite. Others are called iron meteorites, which contain 50% silicate and 50% ferronickel. Orientation can be further divided into two subgroups: olivine meteorite and mid-iron meteorite. According to the composition characteristics of silicate minerals, the iron meteorites are divided into four types: 1) olivine meteorite (type symbol P), which is mainly composed of olivine and iron-nickel metals forming the matrix; 2) medium iron meteorite (M), which is mainly composed of plagioclase, pyroxene and iron-nickel; and 3) paleocopper-scale iron meteorite (S), which is mainly composed of iron-nickel, paleocopper-pyroxene and scale quartz; (4) Olive-bronze iron meteorite (Lo) is mainly composed of iron and nickel, olivine and bronze pyroxene. The content of Ni and Fe in olivine meteorite is about 8-15%. Its composition is similar to that of octahedral iron meteorite. The composition of olivine is Fa12-22 (the percentage of olivine molecule in olivine). The cooling rate of olivine meteorite is lower than that of octahedral iron meteorite. It is thought that olivine meteorite may come from the deeper interior of meteorite matrix or asteroid. It accounts for 2%-4% of meteorites, and the contents of iron, nickel and silicate minerals are comparable (30%-65%). The main minerals are olivine, various pyroxenes, ferrite and nickel.

大多数定向陨石的密度约5.5～6克/厘米^3。在金属铁镍合金中，含镍量多为12%～14%，故出现维德曼构造。也有人根据矿物组成将其划分为橄榄石石铁陨石、古铜辉石鳞石英定向陨石、古铜辉石橄榄石定向陨石和辉石斜长石定向陨石四类。

The density of most directional meteorites is about 5.5-6 g/cm^3. In ferronickel alloys, the content of nickel is 12%-14%, so the Widmann structure appears. According to mineral composition, it is also divided into four types: olivine iron meteorite, paleo-copper pyroxene squamatte oriented meteorite, paleo-copper pyroxene olivine oriented meteorite and pyroxene plagioclase oriented meteorite.