The first step in glassblowing is to heat sand to more than 2000°F (about as hot as the flame of a blowtorch). At this temperature, sand becomes molten and can be easily shaped. Glassblowers use a tool called a blowpipe, which is a pipe about four feet long and made of metal. The glassblower dips one end of the blowpipe into molten glass and then blows on the other end to create a bubble. The pipe is turned and more glass is added and blown until the bubble is the right size. The pipe has to be rotated constantly so that the bubble doesn’t become lopsided.
Once the bubble is big enough, it is shaped using a variety of tools, including a marver, a flat surface on which to roll and shape the glass. Additional instruments include a wooden tool called a block, a bladed tool called a jack, and tweezers. More glass can be added to make shapes, and metals can also be added to make different colors.
When a glass piece is finished, it is cooled down very slowly in a process called annealing. This takes about 24 hours, and it makes the glass stronger. Once the glass is completely cool, it is ground and polished. From there, the glass can be etched and detailed.
-Excerpted from "Arts n' Crafts" by Joey Jersey
Which information is explicitly stated in the passage?
Hard glass cannot be easily shaped.
Adding metals creates different colors of glass.
"Annealing" is an archaic word with Old English origins.
Glassblowing tools have not changed over time.