My guess is that Cult Pens has quite a cult following in the UK. They apparently stock nearly everything they can get their hands on in the way of pens of all kinds, many inks. I have a feeling that if I spent much time on their website I'd end up with a fairly expensive cart of booty. Well they have Cult Pens ink made by Diamine. These are the "Deep Dark" inks, and they are not rebranded standard Diamine inks. The Deep Dark Brown has been rated by those in the know as the closest to the long-discontinued Parker Penman Mocha. But I personally could never justify to myself to order just a couple bottles of ink given the exchange rate, and added shipping costs.
Thankfully an FPN friend sent out some samples of a couple of these inks. This is the Deep Dark Orange. And I will tell you that at $1.23/£1 an 80 ml bottle of Diamine retails for £4.92, about $6, compared to nearly $15 in the US. I'm not sure there'll be nearly $9/bottle of shipping charges. So some bargains may be had for the adventuresome inky pirate.
I love the color of this ink, it reminds me of blood orange. The color is really nice and rich, not bright, deep and not thin. There's nice shading. Excellent handling, with very good flow and lubrication. There could be some sheen on Tomoe River, but you might need a wide nib to really bring that out.
I'm not normally an orange or red ink fan, but for some reason this ink makes me go oo la la. This probably wouldn't become an everyday ink, but would be a joy to use whenever brought into rotation. If you live in the UK, you are one lucky person. The only downside is it's not very waterproof.
Pen: Edison Nouvelle Premiere (M-steel)
Papers: MvL=Mohawk via Linen, TR=Tomoe River, Hij=Hammermill 28 lb inkjet