Invisible Marble Deposit

[Alryno]

Although still appears to be working the marble deposit in the first sector has gone invisible. My geologist still finds it once depleted and strangely I didn't have to demolish it. The other 2 deposits in another sector appear to be working normally.

First screenshot shows the invisible deposit in the first sector.

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This second screenshot shows the other 2 working normally in another sector.

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[Dilbe]

How do you know it is invisible and those marble masons are not just working on the marble deposit in sector 5?

[Alryno]

Because I could not see it as shown in the first screenshot, however it has mysteriously re-appeared as in the screenshot below. I think it must just have been a problem with flash.
I have noticed other glitches like sometimes the number (next to each tree) of trees in each plot shows up sometimes and when I zoom out or just move around the figure doesn't show.

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