Sub Macro1()
Dim WB As Workbook
Dim WS As Worksheet
Dim myCell As Integer
Dim myWhite As Integer, myGrey As Integer

Set WB = Application.ThisWorkbook
Set WS = WB.ActiveSheet
myWhite = -4142 ' None Colored
myGrey = 16     ' A shade of grey

'Debug.Print WS.Cells(9, 3).Interior.ColorIndex

For i = 2 To 12
    myCell = WS.Cells(i, 3).Interior.ColorIndex
    If myCell <> myWhite Then
        WS.Cells(i, 1).Interior.ColorIndex = myGrey
        Debug.Print WS.Cells(i, 3).Interior.ColorIndex
    End If
Next
  
End Sub