– Streak is the least useful property for identification because it does not work for minerals with metallic lusters. -Density is the least useful property for identification because different specimens of the same type of mineral can vary in size.
What is the least reliable way to identify a mineral why?
Color is the least reliable property for mineral identification. The same mineral can come in a variety of colors and different minerals can be the same color. The color can change over time do to weathering.
Which is the least useful test that is used to identify a mineral and why?
The color test is the least reliable test because many different minerals have similar colors. A similar test to color is the streak test. The streak test matches the color of the mineral’s powder. Interestingly, the mineral color and the streak color are often different.
What mineral is black splintery?
The kind of mineral is hornblende .
What mineral is pink or white wavy lines right angles 2 cleavage planes?
The mineral that is pink or white, has wavy lines right angles, and two cleavage planes is Orthoclase . Orthoclase represents an essential mineral of polysilicate, that shapes up an igneous rock.
What is the most reliable way to identify a mineral?
The physical properties of minerals are determined by the atomic structure and crystal chemistry of the minerals. The most common physical properties are crystal form, color, hardness, cleavage, and specific gravity. One of the best ways to identify a mineral is by examining its crystal form (external shape) .
What are the 7 ways to identify minerals?
Most minerals can be characterized and classified by their unique physical properties: hardness, luster, color, streak, specific gravity, cleavage, fracture, and tenacity .
How do I know what minerals I have?
- Look at it closely on all visible sides to see how it reflects light.
- Test its hardness.
- Identify its cleavage or fracture.
- Name its luster.
- Evaluate any other physical properties necessary to determine the mineral’s identity.
Which mineral is black?
| Mineral Name Color Streak Color | Aguilarite # black black, grayish | Pseudobrookite # black brown | Bracewellite black brown, dark | Loparite-(Ce) # black brown, reddish |
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How can you tell if a mineral is black?
Look for glossy black or dark green crystals and cleavage fragments forming flattened prisms in cross-section (corner angles of 56 and 124 degrees). Crystals may be short or long, and even needle-like in amphibolite schists. Characteristics: Glassy luster; hardness of 5 to 6.
Which is the best indicator of minerals true color?
Streak – the color of a mineral in powdered form. Good indicator of a minerals true color because the streak is not affected by air or water.
How do you identify mineral cleavage?
To determine the angle of cleavage, look at the intersection of cleavage planes . Commonly, cleavage planes will intersect at 60°, 90° (right angles), or 120°. Be cautious when you see a flat surface on a mineral – not every flat surface is a cleavage plane.
What is the softest mineral?
Talc is the softest and diamond is the hardest. Each mineral can scratch only those below it on the scale.
Which two minerals are softer than a human fingernail?
| MINERAL NAME LUSTER (appearance) HARDNESS | Fluorite Non-metallic (purple, green, yellow) Softer than glass | Calcite Non-metallic Softer than glass | Halite Non-metallic Softer than glass | Gypsum Non-metallic Softer than glass and softer than a fingernail |
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What are 3 uses for minerals?
Energy minerals are used to produce electricity, fuel for transportation, heating for homes and offices and in the manufacture of plastics . Energy minerals include coal, oil, natural gas and uranium. Metals have a wide variety of uses.
Why is color often an unreliable property for mineral identification?
Explanation: It is common for one mineral to be naturally found in more than one color. ... Using color alone to identify a mineral could lead to an inaccurate conclusion . The hardness of the mineral, luster, cleavage, fracture, how it reacts to an acid, and other traits can be used to identify what the mineral is.
