welcome to HCM,
as per the descrition you have been giving,
i suspect the skin condition of yours will be
1. DARK PATCHES AROUND NOSE AND MOUTH POINTING TOWARDS A CONDITION CALLED MELASMA
OR IT MAY BE PHOTO-PIGMENTATION , DUE TO EXCESSIVE EXPOSURE TO SUN-LIGHT
2. DARK SKIN IN THE SHAVING AREA OF BEARD POINTING TOWARDS- POST-INFLAMMATORY PIGMENTATION, EITHER DUE TO ROUGH SHAVING OR REVERSE SHAVING OR USAGE OF CHEAP QUALITY TRIMMERS
any how you need to be exami9ned properly and should be seen directly by eye to know the level of pigmentation u have and perfect treatment required for you...
i advise you to consult a dermatologist
for further evaluation and treatment..until then start using good non-oil based sunscreen lotion ..
MANY OF NEWER TREATMENT MODALITIES FOR UR CONDITION..MOST EFFECTIVE IS CHEMICAL PEELING...
CHEMICAL PEELING WITH SLC peel system (salicylic acid
+lactic acid +citric acid ) will be more effective for u....