The main device (symbol) in the Cambrige blazon is the saltire engrailed. The two main tinctures (colors) are argent and sable.
Argent is the heraldic metal Silver and is usually shown as very pure white. It is also known more poetically as pearl, moon (or luna) 1Understanding Signs & Symbols – Heraldry, S. Oliver & G. Croton, Quantum, London, 2013, P53. In a sketch or drawing it is represented by plain, unmarked paper 2A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1847, P11.
Sable, the deep black so often found in Heraldry is believed to named from an animal of the marten family know in the middle ages as a Sabellinœ and noted for its very black fur 3A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Sable. In engravings, when colors cannot be shown it is represented as closely spaced horizontal and vertical lines, and appropriately is thus the darkest form of hatching, as this method is known 4Boutell’s Heraldry, J.P. Brooke-Little, Warne, (revised Edition) London 1970, P 26. Although it may seem a sombre tone, and does indeed sometimes denote grief, it is more commonly said to represent Constancy 5The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P35.
The saltire, whilst frequently associated with Scotland is actually a widely used and popular ordinary found throughout all of British Heraldry, perhaps because of its cross-like form 6Boutell’s Heraldry, J.P. Brooke-Little, Warne, (revised Edition) London 1970, P 42. In order to allow for clear differences between similar arms, heralds designed a series of decorative edges, not all of them are appropriate for the saltire (because of the interior angles) but those are suitable can be very effective artistically. The pattern engrailed works well here. It is a series of scalloped indentations with the points facing outwards – and should not be confused with invected, which has the points facing inwards! Wade believes that both of these indented forms represent “earth or land”, and one perhaps can indeed see the furrowed earth embodied in them.