Question About Auction Listing

That is a good question @rec. I think that each of these minted coins out of both metals, although perhaps billon in some cases like the Delhi Sultantate. Maybe you could ask the auction house for a picture or more complete description? Is it SARC maybe?

I agree that it's impossible to know. You might plug in the names of the various issuers (Khwarezm, Sultantate of Rum, Mamluk, etc) into Coin Archives and see what the most common compositions are. Because the listing uses the word silver before bronze, you could expect a fair number will be silver, especally because it is such a repuatable firm. But no guarantee.

But I think as spence said, the best approach is to just send a note asking how many silver coins there appear to be in the lot.
Most places will answer a question on a lot they expect to go for a few hundred bucks. I've asked a question and gotten an answer on a much smaller (and less expensive) lot (from a German auction house).

@rec, ok I still say that there is no way to know for sure, but I might be able to shed a little light on your question. I located the SARC auction where this lot was sold, along with four other similar ones seemingly put together by the same dude (Edward Rataj). He seems to have assembled his collection into 3 ring binders with a separate page of information devoted to each coin. Each of the five lots was accompanied by a sampling of three photos. Of these 15 photos, one is of the outside of the binder, while the remaining show individual coin pages. Across these five lots, the split was 7 silver coins and 7 copper/bronze coins. If SARC chose the pages at random, you might conclude that roughly half the coins in any one lot were silver and half were bronze. More likely is that they picked better than average pages to show.

On the specific lot that you are mentioning, none of the three coins pictured were silver (see below for an example). I'm not sure if SARC would keep the records on the specific coins in these lots, so you might have to reach out to the winner of this lot from June in order to get a definitive answer.