This week, the overall grades of 3 Metals & Mining stocks are lower, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

BHP Billiton Plc Sponsored ADR (BBL) gets weaker ratings this week as last week’s D drops to a F. BHP Billiton Plc Sponsored ADR is a natural resources company that is engaged in the petroleum, aluminum, base metals, iron ore, diamonds, specialty products, stainless steel materials, manganese, metallurgical coal, and energy coal sectors. The company also gets F’s in sales growth, operating margin growth, earnings growth, and earnings revisions. For more information, get Portfolio Grader’s complete analysis of BBL stock.

Constellium NV Class A (CSTM) slips from a C to a D this week. The company also gets F’s in operating margin growth, earnings growth, earnings revisions, earnings surprise, and free cash flow. For more information, get Portfolio Grader’s complete analysis of CSTM stock.

Avino Silver & Gold Mines Ltd.’s (ASM) rating weakens this week, dropping to a D versus last week’s C. Avino Silver & Gold Mines Ltd. engages in the acquisition, exploration, and development of mineral properties in Canada and Mexico. The company also gets F’s in earnings growth, earnings surprise, and free cash flow. For more information, get Portfolio Grader’s complete analysis of ASM 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.