The main device (symbol) in the Knotsworth blazon is the lozenge. 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.
For easy recognition of the items on a coat of arms, and hence the quick identification of the owner, bold simple shapes are best. Hence, simple geometric shapes are often used for this purpose 6A Complete Guide to Heraldry, A.C. Fox-Davies, Bonanza (re-print of 1909 Edition), New York, 1978, P146xz`, and the lozenge Is a typical example of this, and can appear in any of the main heraldic tinctures. It can appear on its own, voided (with the background visible through the middle), and can also be conjoined, whereby adjacent lozenges touch point-to-point. 7A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Lozenge Guillim groups the lozenge with all square shapes as being symbolic of “verity, probity, constancy and equity”. 8A Display of Heraldry, J. Guillim, Blome, London, 1679, P262