Alanus de Rupe and the Beads of Death :)
Looking through my notes, I saw that I'd written on the list of future projects "Ulm, p.112." Well, first I had to figure out which book I'd meant... but eventually I found what I'd been thinking of on p.112 of Stories of the Rose (IMHO, the best book on rosary history in English).
It turned out to be a reference to Alanus de Rupe's Unser lieben frauen psalter, one of the first printed rosary books (1483). In the tenth "Exemplum" (anecdote) in that book, de Rupe mentions a particular rosary prescribed by St. Dominic for a penitent knight. Stories of the Rose describes this as telling how "a knight was instructed to make a set out of five stones" whose colors and symbolism are detailed. Five beads, I thought: oh, that will be easy.
After a bit of investigating, I discovered that one of the manuscripts of de Rupe's handbook is available to me on microfilm at the local university library, so I went to take a look.
Much to my surprise, this seemed to offer a rather different description. The 15th-century German isn't easy (I'd swear they had letters in their alphabet I'd never seen before!), but thanks to a couple of very helpful correspondents, here's a translation.
"In the next-following figure is a paternoster that has five large stones, and after every one large stone should be ten small. The first large stone of the five is many-colored and signifies the multiplicity of your sins. The second stone is light colored, and signifies the uncertain death that is in your certain future. The third stone is red, and signifies the Last Judgement at which you must give an account of your life. The fourth stone of the five is black, and signifies hell. The fifth stone of the paternoster is gilt, and signifies the glory and joy of the saints: which glory and joy is promised to those who keep the commandment of God."
Clearly the description in Stories of the Rose should have said "a knight was instructed to make a set with five stones." After each of these follow ten ordinary Ave beads, just as in a normal rosary; the only thing different is the five specially colored gauds or marker beads with their symbolism. I wasn't 100% sure of my translation, but I mustered up enough courage to write to the author of Stories of the Rose, Anne Winston-Allen, who wrote back very cordially and agreed I was correct -- always a thrill to the amateur researcher's heart!
I had a string of rock crystal (clear quartz) Aves that was just waiting for the right project, so after considerable "creative shopping" for just the right gauds, I was able to create this reproduction:
The "multicolored" bead is a millefiori glass bead from a Venetian importer. The light-colored bead is a natural agate, the red is coral, the black is glass, and the gold bead is another imported bead from Venice, made with real gold foil.