Any recommendations for a pen for writing on dark printed paper?

you can get gold or silver ink pens at any good stationery shop... highly reflective, won't rub off, not too expensive... i think it'd suit your needs perfectly

I've had great success with gel pens. Check your local craft store - most of them sell great gel and marker pens individually as well as in sets, so you could afford to get 2 or 3 where you can't afford the whole set. Also ask the employees at the craft stores. Michaels prefers to hire employees who do the crafts - and gives incentives so the employees will test out the materials. They usually have a good idea as to the best products.

You could use silver or gold ink, both of those work quite well on black or dark paper.

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