Only graphite pencils were made in the early days and the strip or lead consisted of pure Cumberland graphite. This was simply cut to roughly the required shape and inserted into the pencil groove. However, stocks of Cumberland graphite dwindled in the early 1800s and imported graphite was used instead. This was often clogged with grit and sand particles which had to be removed by crushing the graphite, then sifting and cleaning it. The graphite particles were then heated and compressed into oblong slabs.