public CIMTextSymbol ConstructTextSymbol( 
   CIMPolygonSymbol symbol,
   double size,
   string fontFamilyName
)

QueuedTask.Run(() =>
{
  //using the default font
  var textSym1 = SymbolFactory.Instance.ConstructTextSymbol();
  var textSym2 = SymbolFactory.Instance.ConstructTextSymbol(
                     ColorFactory.Instance.BlueRGB, 14);

  //using a specific font
  var textSym3 = SymbolFactory.Instance.ConstructTextSymbol("Arial");
  var textSym4 = SymbolFactory.Instance.ConstructTextSymbol(
                    "Arial", "Narrow Bold");

  //or query available fonts to ensure the font is there
  var all_fonts = SymbolFactory.Instance.GetAvailableFonts();
  var font = all_fonts.FirstOrDefault(f => f.fontName == "Arial");
  if (!string.IsNullOrEmpty(font.fontName))
  {
    var textSym5 = SymbolFactory.Instance.ConstructTextSymbol(font.fontName);
    //or with a font+style
    var textSym6 = SymbolFactory.Instance.ConstructTextSymbol(
                                    font.fontName, font.fontStyles.First());
  }

  //overloads - font + color and size, etc
  var textSym7 = SymbolFactory.Instance.ConstructTextSymbol(
                  ColorFactory.Instance.BlueRGB, 14, "Times New Roman", "Italic");

  //custom symbol - black stroke, red fill
  var poly_symbol = SymbolFactory.Instance.ConstructPolygonSymbol(
    SymbolFactory.Instance.ConstructSolidFill(ColorFactory.Instance.RedRGB),
    SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlackRGB, 1));
  var textSym8 = SymbolFactory.Instance.ConstructTextSymbol(
          poly_symbol, 14, "Georgia", "Bold");

});