Specifies the kind of pen that should be used to draw the minor grid lines. Set Pen to specify the pen to use for drawing minro grid lines in the chart. The value of Pen is a TRSPen object, which is TPen in VCL and TStrokeBrush in FMX. Set the properties of the TPen object to specify the color, style, width, and mode of the pen.
The minor grid is only drawn if it is specified in the DrawOptions property.