Polygon Stroke color and Thickness

   
     
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="Microsoft.Samples.Graphics.RectangleExample"
    WindowTitle="Rectangle Example">

  <Canvas>

        <Polygon
        Points="10,110 110,110 110,10"
        Stroke="Black"
        StrokeThickness="4"
          Canvas.Left="150"
          Canvas.Top="150" />
  </Canvas>
</Page>