Smell-O-Vision and clinkers

While searching for a video segment I ran across one of my souvenirs of my last South African trip in 1984. It is a few ounces of stuff from the ash pan of Class 25NC 4-8-4 number 3408 (North British Built). This was while roving through the Bethlehem engine servicing area. I decided ahead of time to collect something from a 4-8-4 and had obtained a small bottle with a screw on lid that I could use(The people at the hotel gave it to me). This engine was cold, but had run during the time we were there. So a few minutes ago I studied it, and found all sorts of stuff that was in that ash pan, including 5-6 good sized clinkers of various sizes. One is all jagged and oddly shapped. Another is smooth and looks like a chunk of coal in color, while another just looks like gravel. Then of course there is a bit of actual ashes in the bottom. The previous thread regarding steam engine smell made me remember I had this, and tonight I took the plunge and opened the bottle for the first time in 32 years. Yes, there was a bit of an aroma, but unlike the smell of burning coal smoke, it was more like regular old ashes. After inspecting the contents, I can see where coal can become a headache with big clinkers blocking the air flow in the firebox. Wonder if there are any clinker stories from NG crews.
Greg
[www.gregschollvideo.com]

PS the bottle was a Coleman's Hot English Mustard label.