Pencils are graded using the ‘Graphite Scale’ which measures the softness/hardness of the lead.
A pencil lead is made from graphite mixed with clay. Graphite is a naturally soft substance and clay is mixed with it to make it harder. This means a lead with a high graphite content is known as a soft lead and pencils with a soft lead will make a dark mark when used.
Conversely, a lead with less graphite and a higher clay content is known as a hard lead and will make a lighter mark.
Soft leads are graded using the letter ‘B’ to designate how ‘black’ the mark they make is. Numbers are then used to indicate the degree of softness - the higher the number the softer the lead and the blacker the mark. For example, a 2B lead is softer than a B lead and will produce a blacker mark. A 4B lead is softer than a 2B etc.
Hard leads are graded in the same way, but use an ‘H’ to show how ‘hard’ they are. A 2H is harder than an H and a 6H is really really hard.
HB (hard black) leads are considered to be the happy medium on the graphite scale. There are no specific industry standards that set down how black HB leads should be, so an HB pencil made by one manufacturer will not necessarily leave the same mark as an HB pencil from a different manufacturer.
In the promotional market, most pencils are supplied with HB leads. If the blackness of the mark is important, it’s always best to ask for a sample prior to placing an order as leads can vary. If required, we are able to supply a choice of pencils with softer leads, please either contact us or click here for more details.