This marble is TRULY the definition of a gem, because it actually has a crushed up gem inside of it! Those bright little ruby jewels you see inside the marble is a type of material called 'Solid State Frit', and it is made from crushing up synthetic gems, in this case a type of ruby, and it has wonderful properties that work oh so well when encased like this. For starters, they can withstand the extreme heat of melting boro and so they don't melt into clear glass and you're left with these little jewely gems inside. On top of that though, these little beauties seriously light up with a black light! Josh highlighted this property by incorporating the frit behind a blinging UV reticello, and the result is absolutely FANTASTIC. I don't have one this sweet in the collection, and it is killing me to let this gem-quality beauty go! Signed 'Sable 2014'.