Button, 6th Jat Regiment Bengal Light Infantry / 9th Jat Regiment, 1885-1901.  
Imperial crown (though more like St Edward's crown) over left facing bugle horn, '6' between strings.  No rim, gilt.  Reverse marked Jennens & Co London.  
From a card of 28 buttons marked Indian Infantry 9th Jat Regiment; 10th Baluch Regiment.  
From a collection of buttons relating to the Indian Infantry excluding Gurkhas, J-L.
From the collection of Maj H G Parkyn.