1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
marishachu [46]
3 years ago
11

would the Color of your sample tell me with certainty that you have an authentic gold sample and not iron pyrite.

Social Studies
1 answer:
Sladkaya [172]3 years ago
4 0

Answer:Tarnish: Most specimens of pyrite, found in nature, will have at least some tarnish on their surface. Nuggets or small flakes of gold are usually bright and untarnished.

B) Color: Pyrite has a brassy color. Gold has a golden to yellow color. Most native gold is alloyed with silver, and if the silver content is high enough, the specimen will have a whitish yellow color.

C) Shape: Pyrite is usually found as angular pieces, and many of them exhibit the faces of a cube, octahedron or pyritohedron. Most gold particles found in streams have slightly rounded edges, but be careful - some crystalline gold specimens can display a crystal habit that is similar to pyrite.

D) Striations: Many crystals of pyrite have fine parallel lines on their faces. Gold crystals do not have striations.

E) Specific Gravity: Gold has a specific gravity of about 19.3. The specific gravity of pyrite is about 5. (All gold found in nature is always alloyed with other metals. These metals have a specific gravity which will reduce the specific gravity of the specimen, but never enough that it approaches the specific gravity of pyrite. Specimens containing a significant amount of gold will always have at least two to three times the specific gravity of pyrite.)

Gold streak

Gold's Streak: A copper penny and a tiny gold nugget on a black streak plate, with a small streak made by the nugget. The copper penny is in the photo to serve as a scale. The tiny nugget weighs 0.0035 troy ounce, and at a gold price of $1200/ozt the nugget, if it were pure gold, would have a gold value of $4.20. The tiny mark left by the streak plate removed about $0.06 worth of gold from the nugget.

Destructive Tests

A) Streak: Gold has a yellow streak. Pyrite has a greenish black streak. Learn how to do the streak test here.

B) Hardness: Gold has a Mohs hardness of 2.5, while pyrite has a Mohs hardness of 6 to 6.5. Gold will not scratch a copper surface (Mohs hardness of 3), but pyrite will easily scratch copper. Gold can be scratched by a sharp piece of copper, but copper will scratch very few other materials. Learn about the Mohs hardness test here.

C) Ductility: Gold is very ductile, and a tiny piece of gold will bend or dent with pressure from a pin or a pointed piece of wood. Tiny pieces of pyrite will break or resist the pressure.

D) Sectility: Small particles of gold can be cut with a sharp pocket knife. Small particles of pyrite cannot be cut.

Chalcopyrite in Dolomite and Quartz

Chalcopyrite in Dolomite and Quartz: Gold-colored minerals can be tested even if they are embedded in a rock. The gold-colored mineral in this rock is chalcopyrite, and a person could determine that it is not gold by poking the gold-colored material with a pin and observing if it dents or breaks. This photograph is by Scott Horvath of the United States Geological Survey. Click to enlarge.

Other Minerals That Can Fool You!

Chalcopyrite and small pieces of biotite mica can fool you. Chalcopyrite (a copper iron sulfide) has very similar properties to pyrite. It has a lower hardness than pyrite (3.5 to 4) and a lower specific gravity than pyrite (4.1 to 4.3), but the same tests can separate chalcopyrite from gold. Chalcopyrite also has a greenish black streak.

Many people are surprised that biotite mica can fool people into thinking that it is gold. This most often occurs when an inexperienced person is panning for gold and sees a bright flash in their gold pan. After chasing the tiny, highly lustrous flake, they think that it might be gold. However, slight pressure with a pin can break the flake of mica, but a tiny flake of gold will bend around the pin.

Explanation:

You might be interested in
Transfer-appropriate processing is likely to occur if a. there is deep processing during acquisition of the new material. b. the
Tanya [424]

<em>Answer:</em>

<em>b. the type of encoding task matches the type of retrieval task.  </em><em>                             </em>

<em>Explanation:</em>

<em>Transfer-appropriate processing</em><em> is also denoted as 'TAP' and is defined as a kind of "state-dependent memory" that significantly shows that memory performance of an individual is not only being explained or represented by the depth-processing but through the relationship that exists between the process of encoded information initially and later on the retrieval process.</em>

<em>The correct answer for the given question is option b.</em>

4 0
2 years ago
Which of the following forms the foundation of the American culture?
PolarNik [594]

Answer:

A. basic values is the correct answer.

Explanation:

7 0
2 years ago
Read 2 more answers
Twenty years after the Roanoke colonists disappeared, settlers at Jamestown heard reports that they were living nearby in the Ch
shepuryov [24]

Answer:

B :)

Explanation:

I did the assignment and got a 100%

6 0
3 years ago
What effect do u think China's geography may have had on the early people who lived there.?
n200080 [17]
They were big headed because they thought they were the center of the earth...like everything was made around them when really they were just cut off from the rest of the earth
7 0
3 years ago
________ focuses on helping an employee make long-term career plans, while ________ addresses an employee's short-term job skill
weeeeeb [17]

Answer:

D Mentoring; Coaching

Explanation:

Mentoring means giving counsellings, advise , encouragement and guidiance to an employee to enable him or her make long term career plans. It is usually practise in both formal and informal sector.

Coaching refers to giving instructions, trainings and educating employee inorder to address employee short term skills. This helps an employee develop skills to be able to meet up with work demand.

5 0
3 years ago
Other questions:
  • Ben-hur: a tale of the christ was written by civil war commander _____. robert lee joseph johnston lew wallace william sherman
    7·2 answers
  • Lincoln's victory in the election of 1860
    14·1 answer
  • What are commuter lanes?
    13·1 answer
  • Market failure occurs whenever? A. free markets fail to distribute resources efficiently. B. goods fail to arrive at a market in
    5·1 answer
  • Matthew and Ryan are devout Christian Fundamentalists and believe that homosexuality is against God's will and that homosexuals
    10·1 answer
  • Why did the framers of the Constitution decide against a system that directly elected the president by popular vote?
    10·1 answer
  • How does today’s food market compare to the food market of the past?
    14·2 answers
  • Where could you find an electronic version of a service / repair manual?<br>​
    9·2 answers
  • When a yellow light is shined on a white surface, why does the surface look yellow instead of white?
    5·1 answer
  • If you were the first president of the USA what are some things yo would try to accomplish
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!