Tandon Gems
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Stones, strands and how to use them.

Short answers first, then the detail. Written from the stock room by the people who pick the strands.

A strand of gray labradorite beads showing blue flashes under a point light.Stone guides

What is labradorite and why does it flash

Labradorite is a plagioclase feldspar whose blue to gold flash, called labradorescence, comes from light bouncing between thin internal layers. To judge a strand, tilt it under one point light and count how many beads show face-up color. More even, face-filling flashes across more beads signals a stronger strand for stringing.

September 5, 2026 · Anish Tandon
A close-up of small to medium gemstone rondelle beads strung on strands.Buying guides

What size gemstone beads should I buy for a necklace or bracelet

Bead size is the bead's diameter measured in millimeters. A 4 mm bead is about the width of a grain of rice, and there are 25.4 mm in an inch. Choose 2 to 3 mm for dainty layering, 4 to 6 mm for everyday necklaces, and 8 mm for classic bracelets. These sizes string cleanly and wear comfortably.

September 5, 2026 · Anish Tandon
A tray of labradorite and rainbow moonstone bead strands showing blue flash and glow under side light.Comparisons

Labradorite vs moonstone how to tell them apart in beads

Both are feldspars. Labradorite shows directional blue to gold flashes from a dark gray body. Moonstone shows a soft blue or white glow from a milky body. What many sellers call "rainbow moonstone" is actually white labradorite. We sort by body color first, then watch how the sheen turns on and off as we tilt the strand.

September 5, 2026 · Anish Tandon
A close-up of gray sapphire faceted rondelle strands.Making with beads

Should I string sapphire beads on wire or silk?

String faceted sapphire on flexible multi-strand beading cable sized to fit your bead holes, because facet edges can cut thread during wear. Use silk only for pearls and other smooth beads you want knotted between each bead. With cable and proper crimps you get strength, clean drape and dependable finishes for daily wear.

September 5, 2026 · Anish Tandon
A strand of faceted pear shaped gemstone beads laid in a gentle arc.Making with beads

What can I make with pear shaped gemstone beads

Pear-shaped gemstone beads work for quick drop earrings, bold fringe or bib necklaces, clustered pendants, Y designs, charm bracelets, ear climbers and ring accents. Most are top- or center-drilled, so they hang cleanly. We stock pear strands in sapphire and tourmaline, plus emerald and moonstone, sold by the strand for stringing or wire work.

September 5, 2026 · Anish Tandon
A person inspecting a gemstone bead strand with a loupe at a show.Gem shows

How to inspect a gemstone bead strand at a show in 60 seconds

Run the strand through your fingers to feel for chips or rough spots. Hold it to the light to see if the color matches across beads. Use a loupe to check drill holes for chipping and centering. Count beads against the tag. Check the ends for any filler beads. Ask the exact stone name and where it was cut.

September 5, 2026 · Anish Tandon
A 15 inch strand of small round gemstone beads laid against a ruler for counting.Buying guides

How many 4mm beads are on a 15 inch strand

We count about 95 to 100 4 mm beads on a 15 inch gemstone strand when beads are touching. Use inches times 25.4, then divide by the bead length along the hole. Deduct about 1.5 inches for clasp and findings when planning a finished piece.

September 5, 2026 · Anish Tandon
A close-up of white and peach moonstone bead strands with soft sheen.Care and durability

Can moonstone go in water, the shower or an ultrasonic cleaner

Plain water is fine for moonstone beads, but pools and ultrasonic cleaners are not. Moonstone is Mohs 6 to 6.5 with cleavage, so internal layers can split from shocks or heat change. To clean: rinse with lukewarm water, use a tiny drop of mild soap and a soft brush or cloth, then rinse, pat dry and air dry flat.

September 5, 2026 · Anish Tandon
Close-up of mixed sapphire bead strands in assorted shapes.Care and durability

Which gemstone beads are hard enough for an everyday bracelet

Use Mohs 7 as the everyday-bracelet line because household dust contains quartz around 7. For daily wear, we recommend sapphire, black spinel, red Mozambique garnet, and amethyst beads. Black onyx sits on the line and needs a gentle finish. Labradorite, lapis, pyrite, turquoise, Ethiopian opal, pearls, and kyanite are better as careful or occasional bracelets.

September 5, 2026 · Anish Tandon
A strand of 3 to 4 mm gray sapphire rondelle beads beside a calculator.For designers and shops

How to price handmade gemstone bead jewelry

Use this rule: materials at per-bead cost plus your labor rate times hours, times two for wholesale, times two again for retail. Get per-bead cost by counting the beads on the strand and dividing the strand price by that count. If the strand is 13 inches, the method is the same: price divided by bead count equals per-bead cost.

September 5, 2026 · Anish Tandon
A strand of Ethiopian Welo opal rondelle beads showing play of color.Stone guides

Why Ethiopian Welo opal is cheaper than Australian opal

Ethiopian Welo opal, found in 2008 in Ethiopia's Wollo province, is abundant and cut in high volume, so bead strands with real play-of-color usually cost far less than Australian material. White body opal looks opaque to milky; crystal body is transparent. Judge fire by flashes of green, orange and blue from several angles across multiple beads.

September 5, 2026 · Anish Tandon
A tray of multi-color gemstone bead strands displayed at a gem show booth.Gem shows

How to prepare for your first gem show

Set a budget. List the stones and sizes you need. Bring cash and a card. Walk the whole floor before buying. Ask every seller two questions: what is it, and where was it cut. Then note prices and booth numbers, compare, and circle back. Use standard 13 to 16 inch strand lengths and given bead counts to confirm you have enough for each project.

September 5, 2026 · Anish Tandon
A close photo of multi-color Umba sapphire bead strands showing pink, green, yellow and purple tones.Stone guides

What is Umba sapphire and are multi sapphire beads real sapphire

Umba sapphire is natural corundum from Tanzania's Umba River valley, known for yielding pinks, oranges, greens and purples from one deposit. Multi sapphire beads are real sapphire, the same mineral as blue sapphire. All colors except red are sapphire, with Mohs 9 hardness. That's why a single strand can show a full, natural color mix.

September 5, 2026 · Anish Tandon
A selection of gemstone bead strands in various cuts and sizes laid side by side.Buying guides

How much do gemstone bead strands cost and why prices vary

Strand price is set by five things, in order: the stone species, the color grade, the bead size, the cut quality, and the strand length. In US retail, amethyst and labradorite rondelles sit in entry to mid bands. Ethiopian Welo opal small smooths run mid to upper mid. Fine sapphire, especially hand‑faceted briolettes, sits high.

September 5, 2026 · Anish Tandon
A strand of gray labradorite beads showing blue labradorescence.Care and durability

Can labradorite go in water

Yes, brief contact with water is fine, and you can wear labradorite daily. It's Mohs 6-6.5, but perfect cleavage means knocks can crack it, and perfume or pool chlorine can dull the surface. Rinse off splashes, pat dry, and let strands air-dry before storing. Clean with warm soapy water only; skip ultrasonic and steam.

September 5, 2026 · Anish Tandon
A loupe beside strands of amethyst, labradorite, and rose quartz beads on a white table.Buying guides

How to tell if gemstone beads are real stone or glass

Use quick checks: temperature (stone stays cool longer), a loupe for round gas bubbles or a mold seam at the drill hole, and natural bead-to-bead variation in color and inclusions. Glass warms fast, shows bubbles, and looks identical. Plastic feels light. Price matters too: a way-below-market strand for the stated stone and size is a red flag.

September 5, 2026 · Anish Tandon
A coiled set of 6 mm and 8 mm gemstone rondelle strands on a beading mat.Making with beads

How many 6 mm or 8 mm beads for an 18 inch necklace

Plan about 66-70 of 6 mm beads or about 50-52 of 8 mm beads for an 18 inch necklace. The clasp and findings take about 1.5 inches. One 15 to 16 inch strand is usually enough for either size. String beads for the remaining length, then attach your clasp.

September 5, 2026 · Anish Tandon
Close-up of faceted gemstone pear and rondelle beads on a soft bead mat.Care and durability

Prevent edge chipping on diamond-cut rondelles and faceted pears

Handle on a soft mat, keep strands tied until the moment you string, and stage beads on low-tack tape or in lidded trays so facets never rub. Add tiny spacer beads or knots to separate rondelles, and use gentle wraps, caps, and wire guards for pears. Store coiled with tissue between layers. Clean with warm soapy water and a soft brush only.

October 3, 2025 · Anish Tandon
Closeup of multicolor gemstone bead strands suitable for earrings and stringing.For designers and shops

How do I allocate a strand's cost to earring pairs and leftover beads?

Treat the strand's cost as cost per usable bead. Cull any beads you would not sell, then divide strand cost by the usable bead count. Assign each earring pair the cost of two beads, and reduce the strand's remaining cost by that amount. Price finished items by multiplying material cost two to three times, then add labor at your hourly rate.

March 19, 2025 · Anish Tandon
A close-up of small faceted chrome diopside rondelle beads showing bright grass green color.Stone guides

Choose chrome diopside strands by size, shape, and what to avoid

Pick 3 mm faceted rondelles for the brightest chrome green. 4 mm can work if the beads are shallow and well cut; 5 mm risks going near black. Choose shallow profiles like small rondelles or thin pears to keep color rich. In 3 to 5 mm, avoid tall chunky cuts, uneven drilling, and strands that look yellowish like peridot or show bubbles like glass.

February 20, 2025 · Anish Tandon
An amazonite 9x15 mm faceted pyramid bead with a small jump ring through the base on a strand.Buying guides

What size bails or jump rings fit pyramid and trilliant gemstone beads?

Measure the drill height, the center of the hole to the nearest edge. Pick a jump ring whose inner diameter is about twice that distance so it swings freely. For example, a .5 mm drill height needs roughly a 1 mm ID. Choose the thickest wire that passes the hole smoothly.

January 25, 2025 · Anish Tandon
A strand of blue chalcedony beads glowing softly against a white background.Stone guides

How to grade translucency in blue and lavender chalcedony beads

Use two quick bench tests. Backlight a single bead with a phone flashlight and sort strands into High, Medium or Low glow by how much light blooms through the body. Then place one bead over printed text; if letters stay readable through the center, it's higher translucency. Choose smooth ovals, pears and teardrops to maximize that inner glow.

May 14, 2024 · Anish Tandon

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