North Borneo 1918 6c with wider surcharge

rare ( stamp on right) as only 1 sheet of 100 printed with surcharge 13mm apart. significantly fewer than the $5 and $10 of which 400 copies existed for each value. probably not reflected in the relative catalogue price. took me quite a few years to obtain my copy but has seen it being offered in recent years by good auction houses.
The stamps of the pictorial issue of 1909 were surcharged and the 2c in excess of its value donated to British Red Cross and the Order of St John. 3 consignments were sent from London and 2 lost at sea due to enemy action.