The main device (symbol) in the Harle blazon is the piles. The two main tinctures (colors) are sable and argent.
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 1A 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 2Boutell’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 3The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P35.
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) 4Understanding Signs & Symbols – Heraldry, S. Oliver & G. Croton, Quantum, London, 2013, P53. In a sketch or drawing it is represented by plain, unmarked paper 5A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1847, P11.
The pile was originally quite a simple shape, being a triangle reaching from the top of the shield down to a point near the lower centre 6A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Pile. A clear example being that of CHANDOS awarded in 1337, Or a pile gules. There is some argument as to the origin, Wade suggests some similarity with the meaning of “pile” in construction (a foundation) and hence that the shape could be adopted by those who have demonstrated some ability in the building trade 7The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P48. An earlier writer, Guillim, perhaps more plausibly suggested that the shape echoes those of a pennant or triangular flag 8A Display of Heraldry, J. Guillim, Blome, London, 1679, P52 The shape is quite distinctive however and became popular, leading to many embellishments to distinguish it from its close fellows, with multiple piles meeting at various points, starting from various edges and with additional decoration, leading to potentially quite complex descriptions!