Hexagonal symmetry, vitreous luster, hardness (H = 7), lack of cleavage, and conchoidal fracture usually serve to identify quartz. It commonly appears clear and translucent, but not always. Quartz is sometimes confused with calcite, beryl, cordierite, or feldspars.
Calcite can occur in translucent masses that mimic the appearance of quartz, but the two minerals are easily distinguished by their hardness and the fact that calcite reacts easily with dilute acids. Quartz is much harder than calcite and, unlike calcite, cannot be scratched by most metal implements.
Jasper agate, chalcedony, chert, are all just different forms of quarts, opal is different as it's much softer, but can be similar in appearance, I have both opalised and petrified wood, they look similar but can tell the difference just by looking at them.
Similar to quartz, soapstone is a natural stone that's low maintenance. However, because it's a rather soft material, it won't hold up as well to the man-made material. Concerto Gray Quartz looks like soapstone with its frost and dove grays and small speckles of charcoal.
If you have a rock that bites into glass and makes a scratch mark like the two at the top of the photo above, then it contains quartz and it is not a meteorite. If your rock does not make a scratch, then the rock is still probably not a meteorite because many terrestrial rocks do not contain quartz.
Scratch test
On a scale of 1 to 10, with 10 being the hardiest, clear quartz has a hardness of 7. Glass, on the other hand, has an average hardness of 5.5. Perform a hardness test by scratching the crystal on a piece of glass. If the glass scratches, the quartz is most likely real.
Corian Solid Surface is a versatile material composed of acrylic resin binder and natural minerals and does not contain silica. It has a seamless appearance, similar to quartz. One of its main advantages is its durability, as it resists stains, scratches, and moisture.
Calcite can look similar to quartz because it's translucent, but quartz is glassy while calcite has a softer, satiny luster. But a quick hardness test will sort it out definitively.
Corian is cheaper than quartz upfront. You can expect to pay between $40 and $65 per square foot for Corian while quartz starts at $40 and can extend well beyond $200 per square foot. Corian will cost more over the long haul due to the material's fragility and poor resale value.
Use a knife to scratch the surface of a countertop. The outcome indicates the hardness of the mineral. If the knife leaves a scratch, the stone is likely marble. If there are no scratches, the stone is likely a much harder stone like quartzite or granite.
Agate is a fine-grained variety of quartz known as chalcedony that shows concentric color banding. The colors in this agate are caused by microscopic inclusions of iron oxide minerals in the quartz.
The difference between quartz and quartzite is simple
Quartz is an engineered, man-made product manufactured in a factory by combining elements of quartz, resin, and pigment. Alternatively, quartzite is a natural stone that forms 100% organically deep within the earth that is extracted in blocks by quarrying.
Apophyllite and clear quartz are both wonderful crystals to look at, each with unique attributes and applications. In some cases, they can even look similar from afar.
Quartz crystals and masses may have the same luster as calcite, but quartz does not exhibit cleavage and will not react with dilute acid. Quartz is also much harder than calcite. It cannot be easily scratched by a nail and quartz will easily scratch a glass plate.
Minerals (or other substances like eggshells and seashells) that are made out of calcium carbonate (or CaCO3) will usually fizz on the first try. When calcium carbonate and acetic acid (vinegar) combine, a chemical reaction takes place and carbon dioxide gas (CO2) is released. That's why you see the bubbles.
Quartz contains crystals that give the worktops a distinctive lustre, while Corian has a speckling that is similar to different types of granite or marble.
Glass too is made from quartz sand! And many other objects from our daily lives use quartz, such as watches and clocks, kitchen countertops, electronics in radios, GPS and computers, even toothpaste!
Every slab of granite or marble is unique. If it is natural stone, no two areas of the stone will look exactly alike. Because quartz slabs are manufactured, they tend to have a fairly uniform color and consistency throughout, with little variation in the patterns and textures.
To determine if it's a legitimate quartz material, use a steel knife to draw on the surface. Genuine quartz will leave behind black lines (traces of steel), while a faux one will reveal white marks, indicating low hardness. The white lines appear because the plate isn't as hard as steel.
When quartz is electrically stimulated it can vibrate millions of times a second. Since timepieces use a vibrating body to keep up time, incredibly fast vibration of a quartz crystal--up to 4,194,304 beats a second opened a new horizon in accuracy.
Test for Quartz 4 – Look for Bubbles
Simple add some white vinegar to the surface area and look for small, frothy bubbles. Small bubbles indicate that the mineral is made of calcite and is eroding under the vinegar.