The Murex was introduced as a full-size follow-up to the Myu, an all-steel “pocket” pen (a configuration which can be seen in Pilot’s Elite and the Platinum PKB-2000). It is probably not named for the ferocious predatory snails, but should be understood as “Myu Rex,” an interpretation aided by the initials on the cap (the Myu had a lone M, if it had anything at all), and by the fact that in Japan it is pronounced and transcribed as “myurex” (ミユーレクス). But it might also have ferocious predatory snails behind it.
The primary difference between the earlier pocket pen and the Murex is that the latter is a more standard shape; the barrel is longer than then section, with the cap in accord. The Murex also has texturing on the section, which enhances grip at the expense of a some of the sleekness of line inherent to a pen with integral point. To my eye, there is also a blow to sleekness brought about by the flattening of the back of the point, in an apparent effort to give a distinction between “point” and “section.”
There are only three variants on the pattern for this pen: one with black trim, one with red which was also somewhat shorter, and one with a little quartz clock built into the cap, the display perpendicular to the top of the clip.
As one may expect from a steel integral point, the writing feel is rather on the stiff side. With that aside, the pen is excellently balanced for writing, although I haven’t tried the clock version, whose extra fittings might make it a little top-heavy when posted. The texturing on the section is functional without giving irritation. The cap should also be held up for praise, with an excellently sprung clip. It is held in place by a trio of sprung studs around the joint; it’s possible that putting the cap in exactly the same place each time its replaced will lead to wear of the the interior fitting the studs hold onto, but one hears no reports of this.
The production codes used by Pilot appear on the underside of the section, near the joint, along with a size indication.
Production Run: 1977 – c. 1983 (the end date isn’t well supported, so don’t insist that it’s right; I don’t). The red version appeared in 1978 and the one with the
compass in the stock clock in 1981.
Cost When New: ¥5,000, which in 1977 was about $19.00, and about $21.00 in 1983. The clock version went for ¥8,000, or about $35.00 (for modern value, try this calculator). While I give dollar values, this is just for comparison purposes, as it seems this pen was only sold in Japan.
Size: 13.2 cm long capped, 14.2 cm posted, 11.7 cm uncapped (full-length black trim version).
Point: Integral with the body.
Filler: Cartridge, capacity approx. 0.8ml. Two different converters should fit; the CON-20 press-bar type (0.7ml) is definite, and the CON-50 piston type (0.5 ml) should but I didn’t check when I had a chance.
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