Hi All
Dating Richardson pieces is not straightforward, especially paperweights. Various incarnations of 'Richardson' family groups ran glass factories from pre-1845 to post 1900. The only documented Richardson paperweight designs are, I believe, early 1900s - but then, there are no documented Bacchus paperweight designs (or Clichy, as far as I know!). One cannot rule out Richardson making paperweights in the 1845 - 1860 period, and IMHO, it would be very odd if they had not produced some at that time. They were a competent business, and would have seen the success others were having with paperweights. I have measured the density of a lot of Richardson paperweights and ink wells, and also some pieces in Broadfield House museum that date to the 1840s. Unfortunately, they are all very similar in density - which suggests that Richardson used much the same glass recipe throughout.
I cannot say with any confidence when this particular weight was made, but my suspicion is that it is earlier than the documented designs - ie 19th century.
Alan