Luster: A mineral’s luster is the overall sheen of its surface – it may have the sheen of polished metal, or that of an unpolished metal that is pitted by weathering – or it may have the sheen of glass, or look dull or earthy, etc.

Color is an unreliable characteristic for identification, as slight impurities can “stain” minerals into misleading colors. equally, or nearly equally, strong in all directions exhibit a property called fracture. The composition and internal crystalline structure of a mineral give it specific physical properties.

Generally, color alone is not the best tool in identification because color can be highly variable. Some minerals can occur in a variety of different colors due to impurities in the chemical makeup of the mineral.

Explanation: Streak is the color of the mineral in powdered form. It is reliable for rock identification because it is essential to most minerals. Color is not really reliable because mineral could be formed with varieties of color, which is an effect of weathering or impurities.

Streak is the color of a mineral’s powder. Streak is a more reliable property than color because streak does not vary. Minerals that are the same color may have a different colored streak. Many minerals, such as the quartz in the Figure above, do not have streak.

Color in minerals is caused by the absorption, or lack of absorption, of various wavelengths of light. The energy state of the electron is related to the wavelength that it absorbs. The bonding in this element affects the energy state of these electrons. Therefore bonds to different elements produce different colors.

The Colors of Minerals The common causes are metal ions, intervalence charge transfer, ionizing radiation, physical effects, and band gaps.

Streak shows the true color of the mineral….Hardness

• Talc.
• Gypsum.
• Calcite.
• Fluorite.
• Apatite.
• Orthoclase Feldspar.
• Quartz.
• Topaz.

Color is rarely very useful for identifying a mineral. Different minerals may be the same color. Real gold, as seen in Figure below, is very similar in color to the pyrite in Figure above.

Many minerals are colored by chemical impurities. Other factors can also affect a mineral’s color. Because color alone is unreliable, geologists rarely identify a mineral just on its color. To identify most minerals, they use several properties.

Soft – can be scratched by a fingernail, Mohs’ 1-2; Medium – can be scratched by a knife or nail, Mohs’ 3-5; Hard – cannot be scratched by a knife but can scratch glass, Mohs’ 6-9; Diamond is the hardest known mineral, Mohs’ 10.

Pros: Like colorless diamonds, black diamonds are very hard and don’t scratch easily. Compared to other black stones (like onyx or black sapphire), black diamonds won’t lose their shine or luster over time. They also have the natural shine of colorless diamonds.

Drop the diamond into the water. True diamonds have high density and should quickly sink to the bottom of the glass. Fake diamonds are not as thick, and therefore, more likely to float in water. Some materials that make up fake diamonds, such as cubic zirconia and moissanite, can sink if they are heavy enough.

When a jeweler talks about a diamond needing to breathe, he is referring to the light needed to sparkle. If the diamond is too covered up, it has no air and will not sparkle. Diamonds don’t always have holes and cz’s are not always covered up.

Cubic zirconia

Moissanite

Diamond Supply Chains for an Ethical Engagement Ring

• Ruby, sapphire, and emerald are very popular and very rare.
• Another option is fair trade certified gold.
• Your best bet for an ethical engagement ring is to choose a reputable custom jeweler like CustomMade.

A white sapphire is a great choice if you are looking to have a traditional diamond look. They are a little more expensive due to the sapphires popularity but are still significantly cheaper than a diamond. A sapphire has an impressive score of 9/10 on Mohs scale of hardness.

Learn about some of our favorite diamond alternatives below.

• Moissanite. Moissanite was first discovered in 1893 by a French scientist named Henri Moissan, who later won the Nobel Prize in Chemistry.
• Sapphire.
• Aquamarine.
• Morganite.
• Emerald.
• Ruby.
• Amethyst.