From my own records I have the following on Charles Steel, 12th Lancers: Born Madras India, 1829. Cornet 15th Hussars 9 Oct 1854;Lieut 12th Lancers 2 Nov 1854; Captain, Unattached list 30 June 1857; Captain 16th Lancers 9 Oct 1857; Captain 17th Lancers 5 Feb 1858. Major half-pay 18 Dec 1860. Lt-Colonel 1 Oct 1871. Retired as Colonel 1 Oct.1881. He was A.A and Q.M.G. West Indies from July - September 1879. Steel died in London 31 January 1909, aged 80. He served (according to Hart's) in the Crimea, medal with clasp "Sebastopol" and Turkish medal. (This is borne out by his Crimea medal being sold by a Yorkshire dealer in 1996).
I have found him in 1891 being a visitor at Down Grange, Basingstoke, Hants, described as a "Colonel, late 17th Lancers).
Co-incidentally, there was a Veterinary Surgeon 1st Class also with the same name, serving in the 12th Lancers from 2 Dec 1859. He was born at Norwich in 1831 and is listed with the regiment in Harts for 1874.
Hope this helps,
Roy Mills Editor "The Lives of the Light Brigade" www.chargeofthelightbrigade.com