From Charles David Badham 5 December 1856

My dear Sir

Our friend Mr Berkeley tells me you are in possession of some very interesting facts or statements respecting the conversion of grey agates in onyxes, by a process similar to that given by Pliny for clarifying connections and that these pretty ring stones are now fabricated and sold in Italy. Have you any Italian or French Memoir on the subject and if so would you favor me with the title of and where it is to be procured as I spent six years amongst onyxes and onyx dealers in Italy and never heard of these pseudo onyxes and as Corsi, in his great work on the stones of the antients, does not mention the discovery of the process I am rather sceptical & very curious to see what has been written on the matter. Prof Veltheim's boast of, and signal failure in, making sardonyxes as good as antient is the last essay I have read. If you will be kindly excuse the trouble, and give me the [illeg.] I desire I shall be much obliged, and thanking you for the same more italico (by anticipation)

& remain,

My dear Sir

Yrs Oblig^y & faithfully

C. D. Badham