In my opinion, it is only the "early" floral-trailed beads that are actually "wedding cake beads." (See earlier posts on this topic.)

It is accurate that some Venetian beads were covered with gold foil, and trailed over this application—and the foil tends to wear-away except under the trailing, As often as not, the gold foil is not much more than a band around the equator. Sometime intact, and sometimes not.

Your explanation of avventurina decoration is mistaken.

Avventurina decoration, in the context of lampworking was TRAILED on. The "copper frit" idea is mistaken.

First, glass and frit are two different things. One makes frit in order to make glass. However, part of making frit is reducing it to powder or granules. If you reduce glass to powder or granules, it does not "become frit." It becomes powderglass. But this distinction is lost upon many people—particularly current beadmakers who have been misguided. I suppose one could get around this if the phrase "fritted glass" were used—meaning "reduced to powder."

Some Venetian beads, such as Sommersos, are decorated with small chunks of avventurina, prior to being overlaid with clear glass. (I watched a beadmaker at the Moretti factory do exactly this in 1991.) But, in general, a thin avventurina cane is used for trailing. And no "frit" is involved.

Also, there is a perception that avventurina glass derives from having tossed brass or copper shavings or granules into the glass, that make it sparkly. It is not so simple. Brass or copper are added to the glass, melted-in, and the glass is allowed to cool very slowly. Whereupon copper crystals precipitate and more-or-less uniformly enhance the glass. On a microscopic level, these millions of tiny crystals are pyramids, or double-pyramids—which is why they glint. This avventurina glass is used variously. In earlier times "cakes" were sold abroad, so that other industries could make or decorate glass beads. It was/is transformed into canes for trailing or lampworking. And chunks of avventurina were often cut into beads by lapidary practices—involving roughing-out, grinding, polishing, and drilling. These beads are routinely called "goldstone." And, as it happened, avventurine quartz was named after the glass, due to a similar appearance.

JDA.