Wear a wedding ring? Then you likely made your vows over a piece of jewelry that created 20 tons of mining waste, polluting the earth with toxic materials like cyanide.

That is, unless you made sure your wedding ring was sourced responsibly — a research task that’s gotten easier, thanks the No Dirty Gold campaign. Since 2004, No Dirty Gold supporters have worked hard to make both consumers and companies aware of conventional gold mining’s huge toll on the environment and people’s livelihoods.

From destroyed rain forests to violent conflicts to horrible working conditions, gold’s image has been tarnished by its dirty mining practices — and the vast majority of gold is still tainted by these socio-environmental abuses. However, the No Dirty Gold campaign’s gaining traction. Today, more than 60 jewelry retailers — representing 22 percent of the U.S. jewelry industry market and $14.5 billion in sales — have signed No Dirty Gold’s “Golden Rules,” pledging to respect human rights and take environmental precautions.

That said, not all gold jewelry from the companies that have signed on to the Golden Rules can be trusted to be totally clean — because companies need only commit “to switching to cleaner gold sources when available” (emphasis mine) to sign on. This means some signatories are just beginning to look into their practices — while eco-leaders already have clean gold practices in place.

To help you figure out which companies’ gold is cleanest, No Dirty Gold’s put together a new report — “Tarnished Gold: Assessing the Jewelry Industry’s Progress on Ethical Sourcing of Metals” — that grades jewelers on 15 criteria, ranging from tracing their supply chain to supporting third-party certification initiatives. Green companies like Brilliant Earth get an A, while even big companies like Tiffany’s that have taken solid steps towards clean gold score a B. Even companies that haven’t signed on to the Golden Rules — like Target, T.J. Maxx, and Harry Winston — get graded. As you may have guessed, those companies got Fs.

Keep all your future gold purchases as green as possible by consulting No Dirty Gold’s grades — or go a step further and consider sticking to jewelry made with recycled metals to avoid unnecessary mining altogether.

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