[Qgis-user] How to define which CRS to use?

[Joris Hintjens]

Hello,

I have a csv file with a list of coordinates. for example one of them:
X	Y
12374462.4355	4877977.8396

notice the (to me at least) strange X coordinate: in the 12millon range.

I know the point should land somewhere near the Kazach town of Shalkya, with coordinates in the EPSG3857 (WGS 84 pseudo mercator) of +/- X: 750800 Y: 5472000 

If I start at 0 lat and 0 long, I’m off about 5000KM.

How can I define which sourceCRS to use? How to treat this dataset for further use?

Thanks for any suggestion.

Joris