I don't think I've ever seen a celluloid brooch of this style that measured this large.  It is nearly 3" across.  It is your classic flowers with enameling.  There is some major wear to the enamel and some verdigris (which can be cleaned up, but as always - I leave that to the buyer), but it is still wearable.  Barely legible, someone has scratched their name onto the back:  'Pat Hansen' and there are numbers which I can't make out and what appears to be 'Calgary'.  The pinstem and c-clasp are present.