I have never seen anything quite like this check before. I can't help thinking that N.C. may stand for Newton Chambers the well known South Yorkshire mine owners. However, the location of this find doesn't tie up with any of their pits that I am aware of. The check could have migrated across Yorkshire with its once owner. I know this happened as I have a metal detector find from Nottinghamshire of a pit check originating from County Durham. Despite my "gut feeling" of this being a Newton Chambers check I must admit that of all the Newton Chambers Colliery and Iron Works checks I have seen they all carry the abbreviated title initials of "N.C. & Co.". That's not to say that all Newton Chambers checks have to follow the same pattern.

Another strong possibility is that the check is from Nostell Colliery which fits better with its find location.

I have seen a couple of varieties of pre 1947 checks from Nostell that are based on the design below, note some of the similarities;

The above illustrated unissued brass embossed check is also 37 mm in diameter. The abbreviations on its obverse stand for Lord St. Oswald Nostell Colliery. Lord St. Oswald was the owner of Nostell colliery prior to 1947. If this is a Nostell check then it must be of a type that is so far unrecorded for this pit .

The reverse wreath design on your find is similar to that commonly used by the check makers Henry Pasley & Sons Ltd. of Sheffield and Manchester . They made lots of pre 1947 Yorkshire checks many of which have one of two different wreath designs on their reverse. I know for certain that most of the better known examples of Newton & Chambers checks, i.e. Rockingham (various shapes and sizes) Parkgate, Grange, Smithywood and Tankersly etc. were made by Henry Pasley & Sons. Pasley & Sons were also responsible for making the pre 1947 checks for Nostell Colliery illustrated above.