Leslie Field indeed refers to an "impressive two-row pearl necklace (...) made from 222 pearls with a clasp of two magnificent rubies surrounded by diamonds that had originally belonged to the ruler of Punjab, Ranjit Singh. After Britain annexed the Punjab in 1849, the pearls were presented to Queen Victoria by the East India Company".
On the other hand, Vincent Meylan, in his book Bijoux de Reines, quotes the list of jewels bequeathed to the Crown by Queen Victoria (as published in another book by Lord Twinning), among them "a four-row necklace of 55, 55, 56 and 56 pearls, from the treasury of the maharajas of Punjab".
As Baxter had noticed earlier on this board, 55 + 55 + 56 + 56 = 222, i.e. the exact number of pearls mentioned by Field. And the origin is the same (Punjab).
So the "Indian pearl" necklace might have been transformed at some time, and can possibly be worn in various versions, with each pearl strand detachable from the ruby and diamond clasp.