Mineral resource classification is the classification of mineral deposits based on their geologic certainty and economic value.
Here's a list of the top 10 most expensive cities in the country, ranked by average monthly rent for a single person: 1. San Francisco, $2,077. 2. New York City, $1,994. 3. Boston, $1,721. 4. Washington, D.C., $1,397. 5. Seattle, $1,288.
(CNN)New York and Los Angeles have shot up the rankings, London has pushed into the top ten, but Singapore is still the world's most expensive city. It's just topped the Economist Intelligence Unit's 2016 Worldwide Cost of Living survey, making that the third year in a row.