As you may know, it is illegal to sell or purchase ivory in the US, unless it can be documented that the ivory is over 100 years old. So fossilized ivory is safe, but most elephant ivory is off limits. Bone has mostly taken ivory's place as an acceptable substitute. I'm okay with bone, because bone beads are largely a by-product of animals used for food. I have a real problem with elephant or whale ivory, because the animals are endangered and because these animals are killed simply for their bone and teeth.
Anyway, bone beads often come from India, and are rather filthy and discolored when they get to my house. I've found a way to get them to a nice, off-white with a minimum of fuss.
The secret is denture cleaner. My daughter uses denture soak tablets to clean her retainer, so we had them around the house. I figured that bone and teeth and ivory are all about the same substance, so I decided to give it a try.
An overnight soak in denture cleaner left the bone pieces smooth, sparkling clean, and a lovely off-white. If you're looking for a darker color, an overnight soak in strong black tea works wonders.
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I decided to try the denture cleaner treatment on some carved jade pendants I had kicking around, just to see what might happen. Interestingly, it wasn't the same as with bone.
The "jade" pendants came clean, with all the dirt and scrunge coming out of the carving (which is what I wanted). However one of the pendants faded from a deep green to white with some red blotches, revealing an obviously inferior dye job. Another green jade pendant came out clean and remained the lovely green color.
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Carved beads that are rather boring looking can be improved with a metallic wax treatment. One such wax is called "Rub and Buff" and can be found in hardware and craft stores for very little money. Use the teeniest amount possible and use a fingertip to rub the substance rather evenly over the bead. Wait a little bit for the wax to harden (maybe 5 minutes), then wipe off the excess with a paper towel or cloth.
Adds a lot of interest and some much needed glimmer to muddy looking brown beads. I used it on a boring brown stone butterfly, and the thing looks great. Rub and Buff comes in about a dozen shades of gold and silver, and I've found that the antiqued gold shades set off the stones the best.
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Vermeil and gold plated beads, while not ideal, can be used in limited circumstances. If you use such beads as spacers, with larger beads on either side, skin oils and rubbing are unlikely to experience wear and look like crud in no time. This scheme can also be used to hold certain metals away from the skin to prevent irritation (nickel is a well known allergen, and is often found in base metal beads). I use all these kinds of beads in give-away bracelets, due to cost constraints.
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Beads are often filthy when you buy them. I've found that many of my beads look a zillion times better when I give them a little bath before working with them. Don't laugh, but my favorite bead cleaning substance is Doc Bronner's Peppermint Hemp Soap. Doc Bronner was a whacked out old dude, but his soap works great, and we always have some in the house. The soap cuts through the packing grease and schmutz, without stripping A/B coating or certain wax treatments on the beads.
If my beads are on strings, I just give them a swish in warm, soapy water, and let them dry on a paper towel. If they're loose, they get a wash in a strainer I bought at the dollar store and then get a paper towel drying. In almost every case, the glitter and finish are greatly enhanced when the beads are cleaned.
BTW, the exceptions to this rule are the artist beads I've bought from lampworkers and polymer clay beaders here in the group. Those beads always come to me looking like they've been cleaned to within an inch of their lives.
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Howlite beads are often sold as a cheap substitute to turquoise, but I've found a way to make their porous nature work for me. I can buy cheap strands of howlite for well under a dollar and dye them myself. So far, I've used unsweetened Kool-Aid, food coloring and clothing dye, and all have worked perfectly. I don't try to fool anyone that these things are other stones, and have been able to make lurid colors not found anywhere in nature.
After the beads have soaked in the dye substance overnight and dried, I give them a dip in Future floor polish (while still on their temporary strands) to seal the color. Voila! cool colors that the kids like, at a price that I like, too.
Hope these odd little hints help a bit,
Kathy N-V