The overall ratings of 3 Metals & Mining stocks are down on Portfolio Grader this week. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Pretium Resources Inc. (PVG) drops from a C to a D rating. Pretium Resources Inc. acquires, explores and develops gold and precious metals resource properties. The company also gets F’s in free cash flow. For more information, get Portfolio Grader’s complete analysis of PVG stock.

Vale S.A. Sponsored ADR (VALE) experiences a ratings drop this week, going from last week’s D to a F. Vale S.A. Sponsored ADR is a Brazil-based metals and mining company that engages in the exploration, production and sale of basic metals. The company also gets F’s in sales growth, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of VALE stock.

Gold Resource Corporation (GORO) declines this week from a D to a F. Gold Resource Corporation explores for gold and other precious metals. The company also gets F’s in earnings revisions, earnings surprise, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of GORO stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.