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Glass beads composed of soda lime glass are essential for providing retroreflectivity in many kinds of road surface markings. [1] Retroreflectivity occurs when incident light from vehicles is refracted within glass beads that are imbedded in road surface markings and then reflected back into the driver's field of view. [ 2 ]
The beads were integrated in Native American jewelry using various beadwork techniques. Trade beads were also used by early Europeans to purchase African resources, [2] including slaves in the African slave trade. Aggry beads are a particular type of decorated glass bead from Ghana. The practice continued until the early twentieth century.
Indo-Pacific beads are a type of mainly tube drawn glass beads which originated in the Indian subcontinent but are manufactured widely in Southeast Asia.These are usually 6mm in diameter, undecorated and come in various colours for example green, yellow, black, opaque red, etc.
A selection of glass beads Merovingian bead Trade beads, 18th century Trade beads, 18th century. A bead is a small, decorative object that is formed in a variety of shapes and sizes of a material such as stone, bone, shell, glass, plastic, wood, or pearl and with a small hole for threading or stringing.
Lampworking-closeup Lampwork glass beads. Glass bead making has long traditions, with the oldest known beads dating over 3,000 years. [1] [2] Glass beads have been dated back to at least Roman times. Perhaps the earliest glass-like beads were Egyptian faience beads, a form of clay bead with a self-forming vitreous coating. Glass beads are ...
The largest size of a seed bead is 1/0 ("one-aught", sometimes written 1/°) and the smallest is 24/0, about the size of a grain of sand. [3] However, seed beads that are size 5/0 or 6/0 are usually called "pony beads" rather than "seed beads"; the next larger class of seed beads, from 3/0 to 4/0, are usually called "trade beads"; the largest ...
The production of beads from imported glass shards, cullet (scraps) and undesired glass beads has a lively presence in the history of Sub-Saharan Africa. Imported glass was either formed by melting such imported glass, potentially adding desired colorants, and then shaping the melt into a bead form; or, by grinding down the imported glass to ...
Glass wool (for thermal insulation) Special optical glass (similar to Lead crystal) Fused silica Germania glass Germanium selenide glass Chemical composition, wt% 74 SiO 2, 13 Na 2 O, 10.5 CaO, 1.3 Al 2 O 3, 0.3 K 2 O, 0.2 SO 3, 0.2 MgO, 0.01 TiO 2, 0.04 Fe 2 O 3: 81 SiO 2, 12.5 B 2 O 3, 4 Na 2 O, 2.2 Al 2 O 3, 0.02 CaO, 0.06 K 2 O