Is there any way to use "orphaned" city-state-specific luxury resources?

Question

I've found a tile which seems to contain Porcelain:

I'm not quite sure how it happened; it seems like a city-state used to be on that tile, but it was somehow removed (I thought cities which are city-states can never be razed). In any case, Is there any way I can add this Porcelain to my luxury resources?

Although it's in my territory I don't seem to have it currently, and the tile doesn't list any improvement it needs to connect it.

Answer 1

That same topic is covered on CivFanatics here. The conclusions they came to are:

• This happens when a city state conquers a city from a major civ. They automatically get their resource placed under that city, but they immediately raze the city, leaving the resource behind.
• There is no improvement that you can build to access the resource (Citadel won't work). However, if you were to build a city directly on top of the resource, you would then get it.

It is likely this will be patched at some point so that the resource does not automatically appear under the city when it is conquered.