diamond

In metal type printing, diamond was a standardized body size measuring 4.5 points, falling between brilliant (3.5 pt) and pearl (5 pt) in the hierarchy of very small fonts. It belonged to the era when type sizes had individual names rather than simple point measurements, each size corresponding to a specific metal body cast by foundries. Diamond type saw use in footnotes, marginal annotations, and densely packed reference materials where readability mattered less than fitting text into confined spaces.

The name itself reflects the whimsical naming conventions of 19th-century typefounders, where small sizes often carried gemstone names: brilliant, diamond, pearl. The progression upward continued through agate, nonpareil, minion, and brevier. These names varied slightly between foundries and national traditions, creating constant confusion. British typographers sometimes used different size names than their American counterparts for nominally equivalent point sizes.

Why it vanished

Diamond became obsolete during the transition from metal type to offset lithography and digital composition in the mid-20th century. Modern typesetting abandons the rigid body-size anchoring that defined metal type. Software allows any point size to be set freely, eliminating the need for standardized intermediate sizes. By the 1980s, foundries stopped casting diamond, and the term disappeared from active use except in historical texts and archival work.

Anyone handling old letterpress equipment, examining vintage type samples, or restoring historical printed materials may still encounter diamond on specimen sheets or in foundry catalogues. The size produces illegible output by contemporary standards and serves mainly as a historical curiosity. Understanding these obsolete size names becomes necessary only when matching replacements for damaged type in restoration work or when reading period printing manuals and advertisements.