The main characteristic of a stained glass window is colour. Robert McCausland Limited uses only the finest European hand blown glasses. This glass is known in the industry as antique glass. The glass is mouth blown into a cylinder. The glass blower dips a long thin hollow tube into a vat of molten silica that is combined with other elements.

Each company has their own special unique formulas. The artisan blows through the pipe and the glob of hot material at the end of the pipe is blown into a form much resembling a large vase. When it is in a molten form, the consistency of taffy, the bottom is removed with a pair of shears. The glass cylinder is detached from the blow pipe. Once the glass has hardened, it is scored from top to bottom with a glass cutter. The cylinder is then broken along the line and then placed in an oven where it is flattened into a sheet of glass. Each sheet of glass is approximately six square feet. Each sheet of glass is unique and has its own peculiar characteristics. Impromptu naturally occurring striations and irregularities in the glass cause the sunlight to refract. This refraction causes the glass to come alive. The brilliance is nothing short of breathtaking. Hand blowing of glass also means that colors can be changed frequently. Thusly, infinite varieties and shades of colour are created. This means that the colour creates interest throughout the window. We use the famous French reds and blues almost exclusively.

Most other stained glass companies utilize machine made glasses. The colour choices are limited and the windows tend to be very monochromatic.

Holding the precious pieces of glass together are lead strips. The lead is in the shape of a letter "H" and the glass fits in the grooves. The lead is very malleable and is easily shaped around the irregular pieces of glass. We produce our own lead came. Once processed into lead slugs using new lead and reprocessed lead to assure strength and fidelity, it is positioned in an extruder. A steel bar powered by hydraulics pushes the lead slug through a dye. We have over 50 dyes. This means that we can create different widths of lines throughout the window thus creating an interesting design. We also have different leads suitable for cabinets as well as any style of window. McCausland windows have stood the test of time. We can still point with pride to many windows in buildings that are well over one hundred years old.