Bead Library: Seed Beads

How Miyuki Glass Seed Beads Are Made | Seed Beads

How Miyuki Glass Seed Beads Are Made

By Caravan Beads and Barry Kahn

In April 2000 I visited the Miyuki glass bead factory in Japan. My tour was fascinating and the information below is what I gleaned from touring the factory. I was not invited to photograph most of the process, sorry. -bk

How Miyuki Glass Seed Beads Are Made

Step One: Raw materials and recycled glass of the same color are mixed and melted in the furnaces. The Miyuki factory has both automatic and manual furnaces operating 24 hours per day. They are on the 2nd floor.

Step Two: When ready, molten glass from the furnaces falls through a hole. The shape of the hole determines the shape of the glass tubes. Compressed air hitting the center of the glass column turns it into a hollow tube of glass.

Step Three: After dropping to the first floor, the vertical tube of falling glass passes under a thick chunk of wood and turns at a right angle to become horizontal. Imagine a vertical length of rope passing under a pulley and then being pulled sideways. The scene in the glass factory is much more dramatic, however. For starters, the glass "rope" is still extremely hot so that it is slowly burning its way through the smoking piece of wood. In addition the tube of glass is actually being pulled over a series of metal troughs by a machine which not only pulls the glass but also cuts it into one meter lengths. The speed of the pulling determines the diameter of the glass tubes. A faster pull makes thinner tubes; a slower speed makes them thicker.

Step Four: The cooled tubes are sorted to make sure that they are the correct diameter for the size beads being produced. Any tubes which are not the correct size will be recycled and remelted to make new glass.\

Step Five: The tubes are cut into beads. As the cutting room is not open to any outsiders, I can't offer further information. I did learn that one Delica cutting machine can only cut 4-5 kgs per day, which is one reason for their high cost. (And contrary to some rumors, Miyuki cannot run the Delica cutting machines faster to keep up with increased demand, with an accompanying decline in quality. Instead high demand just leads to longer waits for production). Delicas are not cut by lasers, by the way, another occasional rumor.

Step Six: Cut beads are mixed with carbon black and reheated to make them round. Delicas are only slightly heated; round beads are heated more.

Step Seven: The beads are washed. Miyuki has their own on-site water treatment equipment.

Step Eight: The beads are heated again to give them a surface polish. Basic opaque and transparent beads are now finished and ready to pack.

Step Nine: Fancier beads - AB colors, silver and color-lined, metallic, etc. - are based on the basic opaque and transparent colors. There are several different locations in the factory where dyes and other coatings are applied. Some beads require multiple treatments which directly influence their final cost. After dyeing or color-lining beads, Miyuki reheats them again to "set" the colors, a step skipped by some bead companies to reduce costs.

About the Author

Caravan Beads and Barry Kahn

Copyright note: This information is copyright 1996-1999 by Caravan Beads, Inc. It may be freely printed, copied, and distributed electronically IN ITS ENTIRETY. Please - no quotes out of context. Any errors, typos, etc. are the fault of Caravan Beads, Inc. and should be brought to our attention - thanks! Feel free to post it on the appropriate bead sites on AOL, Prodigy, Compuserve, etc.
All article text and photos Harlequin Beads & Jewelry unless otherwise noted.
Text and photos may not be used without permession from Harlequin Beads & Jewelry.

Find it FAST

In Harlequin's bead library you will find information on the history of beads, how beads are made and how beads have been used throughout the world.

Many articles include a bibliography to provide you with additional resources. Many of the beading books referenced are available at your local library.

Contribute to Our Library

If there's a beading topic that you'd like to know more about, or you have ideas for our beading library - we'd love to hear from you. Email us your topic or idea and we'll pass your suggestions along to our writers.

If you've written a beading article yourself that you feel would be a valuable addition to our bead library, we welcome your email, as well.

Get Free Shipping
Get Discounts
Site by HEROweb Marketing & Design    Shopping Cart Website powered by MightyMerchant v4.82

Harlequin Beads and Jewelry specializes in Swarovski crystal, pendants and pearls, Czech glass and seed, Japanese seed and gemstone beads, plus a full selection of stringing supplies and jewelry findings.