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I spent a certain amount of time pondering whether this pen should have its own page, or be considered a sub-model of the Diamond.  I’m still not completely sure that I’ve fallen on the right side of the decision, as the Mini is in many ways merely a short version of the Diamond.  The overall look of it and the fact that is shares many components with the larger pen militate in favour of the idea of it being one of that line, but there is one aspect of the Mini which seems to demand that it be treated as a separate model entirely: the name on the back of the cap band does not include the word Diamond.

Whether it is separate branch or or tender stem, the Mini is a relative rarity in the world of modern pens; a small one.  While the Diamond and the Vac are both rather big pens, in keeping with a current trend which seems to favour largeness, the Mini is in the mold of the older “vest pocket” pens.  It’s not dainty, but is rather a usefully compact pen, capable of travelling in relatively shallow pockets and of being tucked away in purse’s side compartment.  Like the better-designed of the vintage pens of this format, of which the earliest Sheaffer Tuckaway springs to mind for some reason, when deployed for writing it is transformed into a full-length instrument.  Indeed, the Mini’s approach is exactly that of the first Tuckaways; to provide cap-retaining threads on the tail.

The Mini is, then, a Diamond which has been compressed and somewhat refined; a major complaint against the Diamond is its poor capacity for posting.  The ink volume of the Mini is enormous, thanks to improvement of the the piston mechanism which is otherwise common to it and the larger pen.  Portions of the section are interchangeable with those in the Diamond as well, so if one applies a little industry point-swapping is possible.

As with previous TWSBI releases, this is a very good pen for the money.  If there is a design issue apt to cause negative comment, other than a knee-jerk “It’s too small”, it is probably the o-ring mounted at the tail of the pen.  It is there to provide some positive friction to keep the cap in place, but when the cap is in carry mode, the exposed rubber is a little odd.  This is, however, the merest of quibbles, certainly not one that affects performance and probably not enough to put someone off the pen if they are otherwise interested in it.

As an item of mere trivia; the Mini is the first of TWSBI’s self-filling pens to come in a version which has no means of checking the remaining ink level.  I have a notion that this colour pattern will prove the least popular, even though it’s the one I chose; the modern piston-filler is expected to have a window of some sort in it.  I don’t have a problem with this state of affairs, being quite used to various vintage pens which are both self-filling and opaque, but I’m also aware that I’m far from common in my pen tastes.

Update: Following the favourable response of buyers to the Diamond 580AL, a Mini AL was brought into production. Like the 580, the aluminum elements are the filler collar and the section

Production Run: Introduced in October of 2012. The Mini AL appeared in 2015. Both variants are in current production.

Cost When New: $50.00, $60.00 for the AL version.

Size: 11.9 cm long capped, 14.2 cm posted, 10.9 cm uncapped.

Point: Steel.

Body: Polycarbonate.

Filler: Piston , capacity approx. 1.2 ml

TWSBI Mini, in the all-black (or “extremely boring”) version. Other colours on release were all-clear and “classic” which has the barrel clear and the other parts black. This pattern was dropped from production early on.

Mini with the cap set aside to show the mirror-image ends of the barrel.



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