Hi,

The Casanova part is found in this article, "The Golden Ball and the Hangman's Tree" by Tristram P. Coffin. I don't have the article but I found this excerpt:

Fifty years ago, Broadwood and Gilchrist laid out enough evidence from Danish and Scottish song to show that maidens wore gold to symbolize their virginity.[11] The good ladies believed that as the details of the cante-fable plot vanished the story became one of a girl who has lost the symbol of her virginity. The next step, to a tale of a girl who is being hung because she actually has lost the virginity itself, is easy, especially when so many ballads offer this radical punishment for feminine indiscretion. Thus Broadwood and Gilchrist were able to explain why that old symbol for unfortunate love, the prickly bush, enters. When the girl at the gallows sighs,

"If I ever get out of the prickly bush,
I'll never get in no more"

we know what she means. However, convincing as the implications of the Broadwood-Gilchrist thesis are, there is one place the whole idea needs shoring up. The golden object in the tale or cante-fable tradition is clearly not a symbol of virginity, although it is a charm about which the adventures of the maid and her lover center. To say that it becomes a symbol of virginity simply because gold represents purity in other Northern European ballads is perhaps, though not necessarily, unconvincing. At least, the whole thing would be a lot better off if we could strengthen our evidence so that the fusing of the "golden ball" symbol with the "prickly bush" refrain would really make sense. In the winter of 1964, Robert F. Carter, a student in one of my ballad classes, read Phillips Barry's very typical analysis of a "golden ball" text of Child 95 in The Critics and the Ballad.[12] At the same time he had been devoting himself to a selection from Casanova's Memoires in a paperback book, Pornography and the Law. The passage tells how the gracious Casanova made golden balls weighing about two ounces a piece to use for the combined purpose of contraception and payment in his dealings certain courtesans.

Richie