Glossary

Here's a list of terms I've used in my blog.  If you don't see a term here and would like to, please contact me and I'll add it.

Alabaster -- a very slightly transparent glass that usually goes opaque in the kiln but may still retain some hint of translucency

Anneal -- to cool hot beads very slowly in a super high temperature oven so that the glass cools at the same speed on the outside that it does on the inside.  This helps keep beads from breaking and can develop color or opacity.

Cane -- the form the glass I use comes in.  Most of the canes I use are like foot-long pencils.

COE -- coefficient of expansion.  Like everything else, glass expands when heated and contracts when cooled.  To what extent this happens is measured as a COE.  Borosilicate glass has a COE of 33.  Window glass has a COE of about 85.  Bullseye glass has a COE of 90 or 96, and the soft glass I use has a COE of 104.  The higher the number, the more easily it melts.  Different COEs mixed in the same bead will result in the bead cracking or even exploding as the glass cools.  No amount of annealing will change this.

Cored cane -- a type of cane that has one glass on the outside and another on the inside.  They may be different colors and/or transparencies and can produce a marbled bead, more so if the bead is manipulated while hot to expose different layers.

Devitrification --  The process where a glass loses its glossy shine and becomes lighter in color and slightly rough.  This is different than the metallic effect produced by heating some glasses, like metallic black and dark silver plum, a second time.

Dichroic -- a coating applied to one side of either clear or colored glass that reflects some light and transmits other.  The effect is a metallic sparkle.  It is usually encased to keep it from being burned in the flame.

DSP --  shorthand for Effetre Dark Silver Plum.  It is very deep purple in the rod form but goes nearly black and metallic when heated, cooled a bit, then gently reheated.  Sometimes the metallic effect is shiny and others it is matte.

EDP -- shorthand for Effetre Orchid, a.k.a. Evil Devitrifying Purple  It is actually an opaque form of gold pink.  It needs to be worked and left alone.  If it is worked for an extensive time, especially at a low temperature (like I use), it goes all whitish and loses its gloss.  It also can burn and go an ugly grey, and doesn't like ivory at all and goes an ugly yellowish grey on the edges.  It is also gorgeous when it turns out right.

Encase --  to apply a layer of transparent (usually colorless) or translucent glass over a bead made of something else.  The effect itself may be what is intended or it may be used to produce a rainbow effect over a reduced glass or silver.  It also might be used to protect a layer of gold or silver fused onto the bead from rubbing off with wear.  Encasing a bead frequently lightens the color of the glass underneath.

Etch -- to soak glass in a very strong acid to remove the top layer of glass.  This produces a matte, satiny finish.

Gather -- the ball of molten glass on the end of a rod.  This is wound around a mandrel to form a bead or blown to form a bubble that can be cooled and broken into shards.  Glass blowers "gather" the glass on the end of their blow pipe to make their art.

Gold pink --  pink or red glass that gets its color from gold salts.  Common examples are Rubino Oro (Italian for gold pink) and Creation is Messy Cranberry.  Technically, Creation is Messy Sangre and the Italian striking reds are gold colors as well, but rubies.  Gold pinks start out light or nearly colorless and the gold color develops when the glass is reheated.  They can burn and form greyish black dots and lines in the middle if heated too hot and they don't like ivory at all.  They make colors with a high copper content separate into neat transparent/opaque layers and because of the gold content are some of the more expensive ordinary colors out there.

Fume -- to burn metal into glass to change the color.  Common examples are the yellowish color silver turns some glasses and the metallic effect gold gives some glasses.

Lentil -- a bead shape resembling the legume of the same name.  It is a round disc with a narrow edge and puffed center.  They are made with a press.

Metal foil -- a thin layer of metal, usually silver.  It is drastically thinner than kitchen foil but can still be cut with scissors and handled fairly easily with tweezers.  It can be left on the surface of the bead, encased under a transparent glass, or melted in for a specific color effect, either encased or not.

Metal leaf -- available in copper, silver, gold and palladium.  The metals used are as pure as possible, except for palladium, which is a platinum alloy.  Copper doesn't stay metallic but turns greenish and sometimes forms tiny bubbles under encasement.  Silver burns off easily but leaves a residue of itself behind.  It can then be reduced for a shiny metallic layer, especially on black, blue, or dark red and possibly encased for a rainbow effect under the clear glass.  Gold leaf also burns off but can be protected under encasement.  It doesn't react with other glasses but will fume color into glass.  Palladium resists burning and doesn't react with much but it is expen$ive.

Milk glass -- a semi-translucent glass.  Creation is Messy produces them in white, pink, blue (discontinued, but lovely) and green.  They are a bit shocky and have to be annealed carefully.

Murrini -- canes of glass that are sliced to form pictures or decorations.  These slices are applied to a bead so the cross-section is visible.

Opal --  a semi-opaque glass.  Most go more opaque when annealed.

Opalino --  a more transparent opal.  VERY sensitive to reduction and overheating.  Also very shocky.

Pastel --isn't necessarily.  This is what the Venetians called their opaque glass.  So opaque dark cobalt blue is a pastel.  These glasses can be shocky and usually melt very soft and hold their heat.

Reactive glass -- usually a glass with a high silver content that does something special when heated a certain way or combined with other glass.  They are usually very expensive but the effects they produce are lovely.  Some are reduced for a metallic effect, some are reheated to make rainbows of color and the silver content in all of them reacts with other colors.

Reduce -- to heat glass in a low-oxygen flame.  This can bring up the silver in some glasses for metallic or rainbow effects or ruin other glasses by altering the color into something undesireable.

Rose cane --  a cored cane with an opaque core and transparent outer layer.  It is usually pink or red but can be made in any color combination.  It can be coiled on the surface of a bead to make a rose-like design or made into a bead for a semitransparent marbled effect.

Shards --  Small, very thin sheets of glass that are produced by melting a gather on the end of a hollow mandrel or blow tube and blowing gently until a bubble is formed.  The bubble is then broken into pieces and applied to a shaped bead.  Any color glass may be made into shards but the most common are silvered ivory and metallic glass like DSP or silver glass.

Silver glass -- another name for reactive glass.  It is called this because of the large amount of silver salt in its formula.

Silvered glass -- usually ivory, this is glass that has pure silver either applied directly to the surface, such as that used in making shards, or folded into the glass itself.  With ivory, the effect is streaks and bubbles of charcoal grey.

Soda-lime glass -- glass made by adding specific salts to the glass' raw material to make it melt more easily.  The COE of the soda-lime glass I use is 104.

Soft glass -- in the context of beadmaking, this is soda-lime glass.  It may or may not be softer than other glasses when cool, but it definitely melts more easily and droops more when melted.

Special -- this is the term used to describe Italian pastel glass of yellow, orange and red color groups.  These glasses can be tricky to use with other glasses, especially when encased.  Care should be taken to anneal them properly and if they are being encased they should be layered over clear first.

Spree -- a flat, round, disc shaped bead with the hole going from one edge to the other.

Striking glass -- either the process of getting glass to assume its final color by heating and shaping it, cooling it, then reheating it gently and evenly, or the glass itself.  Most of the colors involved have either a high gold content or high silver content.  Using striking glass is both one of the most rewarding and one of the most frustrating aspects of lampwork.

Stringer -- very thin canes of glass that are used to apply decoration to the surface of a shaped bead. 

Tabular -- a flat bead with the hole going from one edge to another.  They look like a tablet.

Transparent glass --  glass that light passes through easily with minimal distortion.  Transparent glasses tend to melt a little stiffer and be a little less subject to shock when first heated.  I usually stick thin rods of clear right into the flame with little or no preheating.  Transparent colors require a bit of preheating and if I rush they can pop a bit, but I haven't had an exploding end yet.  On the down side they can take quite a while to shape by gravity and usually need a little help.  Strangely enough, black is considered a transparent (it just has a LOT of pigment) and so is Effetre Mosaic Green, although both look completely opaque when worked.

Twistie -- a descriptive term for a stringer or cane that has been made by melting a stripe of one or more colors onto another cane and pulling and twisting to form a spiral.



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