hi i have a cast iron fire place on the back its got pattern 22 then the dimensions is their anyway of dating the age of the fireplace its been badly restored by the previous owner and i wanted to get it back to its origional condition but without any idea of its age not sure what it would have origionaly looked like

Very difficult to date unless it is in the Foundary markings. The patterns and designs are still being made from Foundary moulds that were in use a 100 years or more ago so some repro are actually not repro at all but a continuing production!
I use to sell these fireplaces and we dealt with Companies in places like Dorset that had been in business for over 200 years.
The Pattern No.22 that you have inscribed is a reference probably to the Foundary Pattern book that they would hold and record for their own purposes.
Mel.

I don’t think having the precise date of manufacture actually helps that much in determining the original style (as Melboy points out, the same pattern was made over a number of years, and in any one year there would be different patterns in manufacture). Much better to match what you have against photographs and actual examples of original fireplaces, then use these to guide the reinstatement of any missing bits, like the tiles, fire basket, bars, damper, and so on. Also, the fireplace could be much more recent than the house, in which case it might be better to source an older one that does match. Could you describe what you have, or post a picture?