Mystery Filter from Minox C

I recently purchased and needed to service a Minox C, due to battery corrosion from the previous owner. The corrosion was verified to only be on the contacts, so all is well that concern. When I opened the case, however, a small tinted filter fell out from somewhere, but there are multiple places where it fits and could have fallen out from.

[small filter is about 2 mm square]

Unfortunately there are no detailed diagrams of Minox C internals online, only the B model, which seems to be well illustrated online.

The filter fits in the two different tracks where the other filters can slide left or right, but I would doubt it goes here:

Does anyone know where this filter goes? It fits nicely in the front, but that would mean it is used full time.

(The forum system calling the links to the photos of this filter "spam like", though it is from Flicker, so I cannot post photos of the questionable items)

Is this only engaged during certain lighting selections or does it fit in the front permanently?

Thanks in advance.

For this you may consult Don Goldberg at dagcam@chorus.net

Hold on a sec...if you push the filter bar towards the lens, do you see a filter coming out and sliding onto the lens? what color is that filter?

Also, check if the UV permanent filter is in front of the lens. That filter is fixed and it can be easily discerned if you look close to the lens. It's basically a piece of faintly tinted glass, glued in front of the lens, also meant as some sort of protection. If you see just the lens without that glass in front of them, that means you have found the UV filter, fallen by accident. In this case, what Martin said, send it to DAG Camera (Don Goldberg).

I think I figured out how to post a photo here. Here is the mystery filter over where I think the possible correct spot is over the light meter. There is a ND filter already in place over the camera lens - the same as you illustrate above - but this filter is about 1/3 the size of the lens filter. In the end, if I do not figure this out - no loss. This was intended to be a project camera to fix up. I have a handle on everything except the location of this mystery filter.

Arrows below are areas that have filters that slide in, but this could technically fit there as well, but I doubt that is where it belongs:

Here is the full camera front, with the shell off, without that small filter: