if you are talking about the chemistry of the problem: a glass has no structure (amorphous state).a cristal (AKA solid state) has structure, in fact a crystal can show X-rays diffraction.
One way to differentiate between crystal and glass is by examining the clarity and density of the material. Crystal is typically clearer and denser than glass. You can also consult with a professional appraiser or jeweler for a more accurate identification.
Throw them at the ground. The glass will shatter. Plastic will not. dont try this at home... It wont hold water.
Most of the time it will. Good crystal always will. You can tell crystal from glass by lightly tapping the side of the glass, vase, or item. When you do this you will get a ringing sound from crystal and a "thump" sound from glass.
Crystal Glass mine (not on most islands, Glass Blower to improve this, Trade or Pillage.
Crystal beads are made from leaded glass, giving them a higher refractive index and more sparkle than regular glass beads. Glass beads are made from silica, soda, and lime, and are generally less expensive than crystal beads. Crystal beads are often used for high-end jewelry designs due to their superior quality and appearance.
Crystal and glass are the same thing. Crystal is glass that contains lead. When lightly tapped it has a sharp ring compared to plain glass.
Crystal glass contain lead.
Diamond is a crystal. Yes.
With so many fake waterford items made, identifying genuine waterford lamps can be difficult. Look for a gold sticker with green seahorse emblem on the bottom, or look for "waterford" etched into the bottom. To tell the difference between a glass fake and a crystal genuine, check for thickness, light, cut, and weight. Crystal is thicker than glass, crystal is clear while glass has a slight yellow or green tint, glass has rougher edges while crystal has a more smooth cut, and crystal is heavier than glass.
Diamond is a crystal. Yes.
To distinguish topaz from glass or quartzes (e.g. citrine), we should observe the hardness. Topaz is a fairly hard gemstone, meaning it is resistant to scratching. It is 8 on the Mohs hardness scale (diamond is 10, sapphire is 9). A scratch test will determine whether a stone is topaz in most cases. You can perform a scratch test by taking a piece of quartz or other material with a hardness around 7 and scratch it against the "topaz". If you don't want to risk the stone scratching, even if it's fake, you can choose to scratch it on the girdle (the unpolished rim around the gem). There is a lot more information on this site: http://www.shopgemstones.com/topaz-treatments-and-synthetics.html
Crystal methamphetamine fits the description of a white glass crystal powder that does not dissolve in water.