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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Earth and Space Sciences · 术语表

什么是 Ore deposit and concentration factor？

又称： ore deposit · concentration factor

Definition 30.1 Primary & Middle School Earth and Space Sciences · 第 30 章 — Resources from the Earth

An ore deposit is a body of rock in which natural processes have concentrated a metal or a mineral enough for it to be extracted at a profit. The concentration factor of a metal is the number of times its content in the ore is greater than its average content in the crust:

\text{concentration factor} = \frac{\text{content in the ore}}{\text{average content in the crust}} .

How many times nature has to concentrate seven metals to make an ore worth mining: the minimum grade of the ore divided by the average content of the crust. Each step of the scale is ten times the one before. Data: D. Perkins and others, Mineralogy, and, for gold, S. Earle, Environmental Geology. — How many times nature has to concentrate seven metals to make an ore worth mining: the minimum grade of the ore divided by the average content of the crust. Each step of the scale is ten times the one before. Data: D. Perkins and others, Mineralogy, and, for gold, S. Earle, Environmental Geology.

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