Selenium toning (and I'm speaking of wet darkroom work here) is what is used on fiber prints to provide longer archival tendencies. Depending on the dilution of the selenium with water, you will also achieve a *purplish* sometimes attractive, sometimes not hue. It really depends on the image, the artists preferences, etc. IMHO none of the above has a selenium toned look to it.... this is what it should look like.... Keep in mind color images are not normally toned in selenium... converted to bw and selenium curve added. This is the straight curve, you can add more or less to taste. Rich dark brown tones are different (which you mention in your original post)..... sepia toners, or a straight brown toner, would create that look that I think you are trying to achieve.... I think.

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