Copperplate — pointed pen
The pointed-pen hand: 55° slant, 5 mm x-height, shade on the downstroke, and the oval that a third of the alphabet is built from.
Copperplate minuscule a: four pen movements and one pressure rule
The engraved scripts of the eighteenth century were cut with a burin, and the pointed-pen hands that imitate them today are built on a single rule: pressure on the downstroke, no pressure on the upstroke. The minuscule a is the shortest complete demonstration of that rule, because all four of its movements are visible in a single 5 mm x-height letter.
The copperplate oval: one shape that governs a third of the alphabet
a, c, d, e, g, o and q are all built from the same oval. In copperplate it is not a circle and it is not tilted by eye — it is an ellipse whose major axis lies on the 55° slant line, with a long-to-short ratio of about 5 : 3. Get the oval right and a third of the minuscule alphabet falls into place; get it wrong and no amount of letter-by-letter practice will make the page look even.