It bothered me that I was throwing away so much plastic. Every time I finished a cheap biro, I threw away not only the part that contained the ink, but also the outer casing and lid as well.
Could I not just replace the bit I'd used? No, apparently not. The inners are not sold separately.
I looked into refillable pens, but without much success unless I wanted to invest in something more expensive. It grates to have to spend more money on refills than I would on pens, when I was just trying to reduce plastic waste.
Then, while looking for something else in the loft, I found...
... my old fountain pen! Hooray!
When I was at primary school and learning to write, at some point in our efforts to master joined-up writing, we were permitted/encouraged to get a fountain pen. This followed the progression from pencil to biro, which was permitted when we reached a certain competence. My friend Amanda decided that she preferred being able to rub out her mistakes, so she went back to pencil, which threw off the reward structure somewhat.
Anyway, I'd found my old fountain pen, which I hadn't used for years. Even better, it had an empty cartridge in it. Because I object to disposable printer cartridges even more than disposable pens, I have ink and a syringe for refilling cartridges, so I used that to fill the pen cartridge, just to see what it was like to write with. It was lovely, though printer ink is rather thin, so it bled through the paper a lot.
I bought a couple of packs of cartridges and switched to using the fountain pen instead of disposable pens. Great! But... there's still that plastic cartridge getting thrown away every time I run out. Actually, they weren't, because
I never throw anything away I'd had an idea. If I could refill one cartridge to test the pen, why not do that as a matter of course?
The printer ink refill kits had come with packs of little bungs suitable for some printer cartridges. I didn't need them for my printer, but I was sure I had them sitting around somewhere (Throw them away? Me?) After a little searching, I found them and was delighted to find that one set fit the pen cartridges perfectly. With a set of three, I can fill four cartridges at a time, including one that goes straight into the pen. (I later found another set, so I can now fill seven at a time.)
I bought a lovely bottle of ink from the local stationer's (link). At £7 it felt rather expensive, but the cartridges take about 2ml each, so this 57ml bottle is 28 cartridges-worth, which works out at 25p per cartridge, half what they cost as sold by the packet. So it's cheaper, more convenient (no need for a trip to town) and more to the point, I'm not throwing away a bit of plastic every time I run out of ink.