Tonsil stones form in crypts and holes in the tonsil. Here is one that is beginning to form.
Deep in the tonsils food gets trapped down crevices and cracks caused by recurrent tonsillitis. This food is squashed together forming tonsil stones, which then rot and cause a bad taste and smell, triggering sore throats. The treatment is to partly remove the tonsil, so that the crevices and cracks are not deep enough to retain food. The Carbon Dioxide laser under local anaesthetic spray is a very good way of doing this.