The geology of the Gunnar U mine near Uranium City, Saskatchewan, Canada is described by K.E. Ashton (2010).

economy.gov.sk.ca/SO12010V2_A4

The host rock is altered granite. The alteration replaced the original quartz, etc  with albite plus chlorite, hematite, carbonate.

Dear Mr. Bute,

the process can be described in the broadest sense as episyenitisation which is common along faults in granitic rocks hosting U deposits:

DILL, H.G. (1983) Plutonic mobilisation, sodium metasomatism, propylitic, wall rock alteration and element partitioning from Höhensteinweg uranium occurrence (Northeast Bavaria). - Uranium, 1: 139-166 .

DILL, H.G. and KOLB, S.G. (1986): The Großschloppen-Hebanz uranium occurrences. A prototype of mineralized structure zones characterized by desilification and silification. - In: Vein-Type Uranium Deposits (Ed. H.D. Fuchs), International Atomic Energy Agency, 261-274.

Best regards

H.G.Dill

Thank you very much Prof. Dill. I appreciate 

In mediterranean Coastal Rangers near Barcelona we have epidiorites and episyenites explain for Prof Harald G.Dill

Please find enclose, whole rock and ore mineralogical characterizations are very important, crack and fracture structures attribute to seconder uranium mineral formations along the depth. The depth includes oxidation and reduction zones according to element content such as high Eu values are  signature oxidation zone and plus Eh condition.

What type of granite is the mineralization hosted in? Peralkaline? Peraluminous? Metaluminous? Also, I would likely think that these compositional changes are at least in part due to fluid movement along the structures.