Frank, I've recently done quite a lot of Veradon toning over the last 6 mnth and found that if i'm not careful, the print can tend to lose contrast and go more 'milk' chocolate in colour during washing and even after drying, over time. Going out on a limb here I think the reason is that Veradon toning is normally halted at the colour desired, resulting in only partial silver halide conversion.
Originally Posted by FrankB
On Agfa MC111 glossy which is the paper I use most, giving the print a Selenium tone before Veradon seems to work very well. By comparison with just Vrdn toning, these prints haven't changed. Also, the increased DMax counters the reduction by the Vrdn and gives the print an attractive 'richer' quality that I really like. But you've got to experiment a little with timings. Selenium tone for too long and it will convert all the silver halide, and the Vrdn will have no affect. Too little time and the Selenium won't have enough affect. I've been using Selenium this way at 1:10 for about 4-6 mins, this is getting close to giving archival properties.
When I use Veradon toner, I do it outside in good light if possible in a white tray with an quivalent wet print to compare the colour change. Keep checking the print by taking out of the Vrdn and comparing with untoned wet print. Have a tray or washer of water ready and anticipate the colour change you're after because it will continue to change for a little while during the final wash.
edit: also a peg helps (for the nose )