Introducing Glas. Glas is the Gaelic word for grey. This base is a blend of all British fibre; 75% Bluefaced Leicester and 25% Masham giving a pale grey colour in its natural state. It is is joy to dye as with this darker base all the dyed shades have a real depth to them. It is squishy and sleek and a plumpy aran weight ideal for quicker and cosy knits.