New Icon Next to Column

Anonymous , to me, seem like a Identity field, key icon. Have marked column as key column 

refer :https://docs.microsoft.com/en-us/power-bi/create-reports/service-the-report-editor-take-a-tour#the-field-icons

 

Under the Model view, you have an option to select a column as Key Column for a Table in properties

Hi Anonymous ,

 

Is this a date column for any chance? This symbol means that the column is marked as a date table.