An AB pencil is not a standard or recognized grading designation for graphite pencils. Instead, pencil grades use a combination of letters and numbers, with 'H' indicating hardness and 'B' indicating blackness. A pencil with the designation 'AB' does not exist within standard pencil grading systems.
Understanding Pencil Grading
Pencil grades are used to indicate the hardness of the graphite core. This impacts both the darkness of the line it produces and how easily it will wear. The grading system generally includes:
- H (Hard): These pencils produce light, thin lines. The higher the number (e.g., 9H), the harder the lead and the lighter the line.
- B (Black): These pencils produce darker, thicker lines. The higher the number (e.g., 9B), the softer the lead and the darker the line.
- HB: This grade sits in the middle, offering a balance between hardness and blackness.
- F: This grade is between HB and H, producing a fine, sharp line.
The Role of 'B' in Pencil Grading
Based on the provided reference, the letter B in pencil grading specifically refers to the blackness of the graphite. This means that a higher B number indicates a softer lead that will produce a darker, more noticeable mark.
Common Pencil Grades
| Grade | Hardness | Blackness | Common Uses |
|---|---|---|---|
| 9H | Hardest | Lightest | Technical drawings, fine detail |
| 2H | Hard | Light | Light sketching, drafting |
| HB | Medium | Medium | Writing, general use |
| 2B | Soft | Dark | Sketching, shading |
| 9B | Softest | Darkest | Art, very dark lines |
Why 'AB' is Not a Standard Grade
Given the established grading system, 'AB' is not a recognized designation. It's possible that the term might be used informally or incorrectly. There may be a misunderstanding of the standard grading. If you encounter a pencil labeled 'AB', it would be best to consider it non-standard or mislabeled.
Conclusion
Based on the provided reference information about pencil grading, a pencil labeled 'AB' is not a standard grade. The 'B' specifically refers to blackness and the standard grades utilize numerical values with H and B, but not together as in "AB."
