Not all minerals are considered gemstones because the designation of a gemstone depends on a combination of factors, including its beauty, rarity, durability, and demand in the market. Here are some reasons why not all minerals are classified as gemstones:
Beauty: Gemstones are valued for their aesthetic qualities, including color, clarity, brilliance, and luster. Not all minerals possess these desirable visual characteristics. Some minerals may be dull, opaque, or have unappealing colors that do not meet the standards of what is considered attractive for a gemstone.
Rarity: Gemstones are often associated with rarity, which increases their desirability and value. While many minerals exist abundantly in nature, only a few occur in gem-quality quantities. The scarcity of certain minerals contributes to their classification as gemstones, as they are prized for their relative scarcity compared to more common minerals.
Durability: Gemstones are expected to be durable and withstand the rigors of everyday wear and handling. Not all minerals possess the necessary hardness, toughness, or resistance to scratching and chipping required to be considered suitable for use in jewelry or other decorative purposes. For example, talc, the softest mineral, is not suitable as a gemstone due to its low hardness.
Market Demand: The perception of value and demand for a mineral as a gemstone is influenced by cultural, historical, and fashion trends. The desirability of certain gemstones can change over time, driven by factors such as fashion trends, marketing, and cultural preferences. While a mineral may have the necessary qualities to be classified as a gemstone, if it lacks demand in the market, it may not be widely recognized or used as a gemstone.
It's important to note that gemstones are a subset of minerals, and the distinction between gemstones and other minerals is often subjective and based on human preferences. Some minerals may be considered gemstones in certain contexts or cultures while not being widely recognized as such globally. If you are planning to buy gemstones online then you can visit the CabochonsForSale they have wide collection of gemstone.
Oyster is a type of aquatic organism that significantly require oxygen for its survival and other metabolic processes.
A Population may be defined as the group of individuals belonging to the same species living in the same area at a particular time period. It includes the members of the same species.
The population of oysters requires at least 2-3 ppm of dissolved oxygen in order to survive in the aquatic environment. But if this amount of dissolved oxygen may alter it may significantly affect the population of oysters.
The higher level of dissolved oxygen is not a reason for much concern, but lower levels may be the potent cause for the reduction of the oyster population within the ecosystem.
Therefore, the Oyster is a type of aquatic organism that significantly require oxygen for its survival and other metabolic processes.
To learn more about the Oyster population, refer to the link:
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A hypothesis is a testable possible explanation, while a theory is an explanation that has been tested extensively.
If you need to learn more and remember about this stuff better, watch the Amoeba Sister's Casual and Scientific Use of "Theory" and "Law". Trust me, it helps!
:)I hope I answered your question well!:)
Answer:
hypothesis, theory
Explanation:
Answer:
1st blank-- villi
2nd blank-- surface area
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