Based on a some off-list emails I just received from well-informed listers, it appears that the 4-leaf-clover is indeed the stamping of the the Union-Berg (or Berg-Union?) spokes. So, they are not Colnago spokes.
Wow, so there is something that Ernesto didn't put his symbol on!
A couple of other people with experience wrote to add that these spokes are chromed and prone to breakage.
Thanks to all who responded.
Ray Dobbins Miami, FL USA
Raymond Dobbins <email@example.com> wrote: A few days ago a Colnago Junior was outed to the list (eBay item # 270149110442). I noticed that the spokes had what looks like the Colnago Ace of Clubs (Asso di Fiori), stamped on the spoke heads:
I've never seen spokes like these before and I'm wondering if they are in fact Colnago branded spokes, or if the stamp is a 4 leaf clover (it's hard to tell), representing some other brand. Does anyone know?
Miami FL USA