Identifying a component

[MrPuhur]

As part of a 40 year old mill's controller board, there's a blown component I couldn't identify. There's a failed (short at the negative side) diode bridge next to it with a smoothing cap and a dead LM309 5V voltage regulator after the diode bridge. The blown unidentified part is across the 5V output of the LM309.

Here's 2 high resolution pictures of it. It has "8012" written on it, but I really couldn't get anything sound based on that.
https://drive.google.com/file/d/1JkcND16nwQNHQei-VI2HTN4_MBCFFrKo/view?usp=sharing
https://drive.google.com/file/d/0B_yAWIhEioTZbjhYQjJiZlZ5SVB4QWtoQmRzVEdiMEdUbm00/view?usp=sharing

[shakalnokturn]

Should be an electrolytic capacitor, the common practice is to place 10μF close to a regulator to avoid it oscillating.
8012 would be the date-code, maybe you have a value on the hidden side.

[fzabkar]

Could it be a tantalum capacitor? These had a habit of failing catastrophically.

[MrPuhur]

Now that you gave me the idea to search for what old tantalum caps used to look like, I found out that acutally very visually similar ones existed. Thanks.

[fzabkar]

These look like the ones I used to see in US made gear in the 1980s (possibly by Sprague):