Anyhoo, my car is covered in a mysterious fine abrasive dust
We normally get quite a bit of fine, wind blow, salt and sand deposit on our cars .... and on the windows of the house TBH but I have just been out back and checked the cars. All three are well covered in a fine dust and it certainly is different from the normal both in texture and colour. Much thicker too. I have not checked the abrasive qualities but will hose it off rather than rub at it.