There are a number of ways to blacken hand-stamped letters. I will discuss several methods and their pros and cons, particularly in relation to health hazards, which is a concern for people with small children who may lick their jewelry. Some methods are safer than the other, but after all, you don't want your kids to lick any kind of ink. So, please keep jewelry out of your kids' reach!
- Pro: probably the cheapest and simplest method. You can roughly draw over the lettering and wipe the charm with a Q-tip with alcohol (or nail-polish remover) to clean up the excess ink. If you have steady hands, precise drawing over the lettering will eliminate the need of cleaning.
- Con: this method isn't long lasting. The color starts fading in about 5-6 months.
(2) Crayon and nail-polish
- Pro: cost effective, and you probably have several at home. Draw over the lettering and clean the excess.
- Con: they tend to flake over time.
(3) Liver of sulfur
- Pro: if you are working with sterling silver, brass, and copper, you can blacken the lettering with a liver of sulfur. This coloring method is long lasting. Dissolve a small amount of liver of sulfur in hot water, and apply it over the lettering with a paint brush. Then clean the surface with steel wool or sanding sponge. Neutralize the chemical by dipping the charm into a baking soda bath. The color of the lettering will be dark grey rather than black.
- Con: a liver of sulfur is quite stinky. There is less stinky solution that is ready to use, such as Black Max. However, both liver of sulfur and Black Max are harsh chemicals, and need to be handled with care. Also, even if you neutralize the chemical with baking soda, charms that were treated with a liver of sulfur/Black Max tend to oxidize faster.
- Pro: this is another long-lasting method, and a wide of range of colors are available. Apply enamel paints that you can find in craft shops (e.g., Testors enamel pains) with a paint brush, and wipe off the excess with Q-tip with alcohol.
- Con: unlike Sharpie, enamels are hard to clean and create a mess. Also, many products (especially enamels for car repairs) are carcinogenic. Read SDS (Safety Data Sheet) information for their health hazards.
(5) Patina - Thumbs UP!!
- Pro: long-lasting, and various colors are available. Choose a patina made for metal. There are some, such as Vintaj Patina by Ranger and Glider's Paste. I personally find it difficult to use Glider's Paste for this purpose (it's a thick, dry paste that you rub onto metal), and use Vintaj Patina. It has a skinny application tip, and I directly apply the patina onto the lettering, and wipe off the excess first with a paper towel, and then with a Q-tip with alcohol. It is less messy compared to enamel paints. It is water-based, but it becomes water-resistant and non-toxic once it's dry.
- Con: so far, I am quite happy with Vintaj Patina. We use the Onyx color.
A large percentage of our customers are mothers with small children. Thus it is very important to us that the ink is non-toxic. However, 'non-toxic' doesn't mean it's food safe, and there probably isn't food safe ink that is long lasting.
So, when deemed necessary, we apply a food-safe, transparent sealant over charms with black lettering. We routinely apply this sealant to all of our gold-plated charms to protect the gold plating, which is more delicate than rhodium plating (silver color).
I will write another article about jewelry sealants!