FAQ & Contact

Mark Sterling is a platform for tracking what gold and silver actually sell for in the real world. We aggregate observed sale prices from auctions, online marketplaces, coin shows, local dealers, and private sales, then compare them to the daily spot price. The result is a dataset that shows the true market premium or discount for different metal types, purities, and forms.

We first calculate the effective price per troy ounce for each observation (total sale price divided by weight in troy ounces). Then we divide that by the spot price on the date of the sale and multiply by 100. For example, if silver sold at $72/ozt and spot was $80, the % of spot would be 90% — meaning the buyer paid 10% below spot.

Melt value is the raw metal content of an item: weight in troy ounces × purity × spot price. Premium over melt is the difference between what was actually paid and that melt value. A positive premium means the buyer paid more than the metal alone is worth (common for collectible coins). A negative premium means they got the item below melt — a bargain.

All weights are converted to troy ounces for consistency. You can enter weights in grams, pennyweights (dwt), avoirdupois ounces, kilograms, or troy ounces and the system converts automatically. For constitutional silver (90% US coins), you enter the face value and the system calculates the troy ounce silver content using standard multipliers.

Yes. Your email is irreversibly hashed (using bcrypt) before storage — we never see it, store it in plain text, or can recover it. There are no tracking scripts, no analytics, and no cookies unless you explicitly opt in to "remember me" on login. Your observation data is visible to you and anonymized in aggregate on the public page. We do not sell or share any user data.

Live spot prices are scraped from silverrecyclers.com and cached for 15 minutes. Historical closing prices come from daily futures data (investing.com) and the GoldAPI.io service. Every day the site is visited, the current spot price is automatically stored to build a growing daily price history.

Yes — Mark Sterling is completely free to use. The public homepage shows aggregate pricing data, ticker cards, and recent transactions with no account required. Creating an account is also free and gives you a 7-day trial with full access to the dashboard, trend charts, and detailed browsing.

After your 7-day trial, you keep full access as long as you contribute to the dataset. The current requirement is just 1 observation per 30 days — log a single real-world gold or silver transaction and you maintain access to the dashboard, trend charts, filtering, and all community data. If you stop contributing, you can still add observations at any time to regain access. The more people contribute, the more valuable the dataset becomes for everyone.

Use the contact form below and select "Incorrect Data" as the feedback type. Include as much detail as possible about which observation is wrong and what the correct information should be.