Chapter 3 - Give It Some Thought - Page 104: 1

a. Gold nugget: Yes, a gold nugget is considered a mineral. Gold meets the geologic definition of a mineral as it is a naturally occurring inorganic solid with a definite chemical composition (Au) and a crystalline structure. b. Seawater: Seawater is not considered a mineral. While seawater does contain dissolved minerals, it is a complex mixture of water and various dissolved substances, including salts, ions, and organic compounds. Seawater does not have a specific crystalline structure, which is a characteristic of minerals. c. Quartz: Yes, quartz is considered a mineral. It meets the geologic definition as a naturally occurring inorganic solid with a definite chemical composition (SiO₂) and a crystalline structure. Quartz is one of the most common minerals on Earth. d. Cubic zirconia: Cubic zirconia is not considered a mineral. It is a synthetic material created in laboratories for use as a diamond simulant. While it may have a crystalline structure, it does not occur naturally in the Earth's crust and therefore does not meet the geologic definition of a mineral. e. Obsidian: Yes, obsidian is considered a mineraloid. Obsidian is a natural volcanic glass formed by the rapid cooling of molten lava. While it lacks a crystalline structure, it is composed of mineral-like substances and is often classified as a mineraloid, a mineral-like substance that does not meet all the criteria of a mineral. f. Ruby: Yes, ruby is considered a mineral. It is a variety of the mineral corundum (Al₂O₃) and meets the geologic definition of a mineral as a naturally occurring inorganic solid with a definite chemical composition and a crystalline structure. g. Glacial ice: Glacial ice is not considered a mineral. Although ice itself is a mineral, the term "glacial ice" refers to a mixture of ice, snow, and air that forms glaciers. It is not a crystalline solid with a specific chemical composition but rather a combination of various materials. h. Amber: Yes, amber is considered a mineraloid. It is an organic substance derived from the fossilized resin of ancient trees. While it lacks a crystalline structure, it is composed of complex organic compounds and is often classified as a mineraloid. In summary, the items on the list that are considered minerals according to the geologic definition are: - Gold nugget - Quartz - Ruby The items that are not considered minerals are: - Seawater - Cubic zirconia - Glacial ice Obsidian and amber are classified as mineraloids, which are mineral-like substances that do not meet all the criteria of a mineral.

a. Gold nugget: Yes, a gold nugget is considered a mineral. Gold meets the geologic definition of a mineral as it is a naturally occurring inorganic solid with a definite chemical composition (Au) and a crystalline structure. b. Seawater: Seawater is not considered a mineral. While seawater does contain dissolved minerals, it is a complex mixture of water and various dissolved substances, including salts, ions, and organic compounds. Seawater does not have a specific crystalline structure, which is a characteristic of minerals. c. Quartz: Yes, quartz is considered a mineral. It meets the geologic definition as a naturally occurring inorganic solid with a definite chemical composition (SiO₂) and a crystalline structure. Quartz is one of the most common minerals on Earth. d. Cubic zirconia: Cubic zirconia is not considered a mineral. It is a synthetic material created in laboratories for use as a diamond simulant. While it may have a crystalline structure, it does not occur naturally in the Earth's crust and therefore does not meet the geologic definition of a mineral. e. Obsidian: Yes, obsidian is considered a mineraloid. Obsidian is a natural volcanic glass formed by the rapid cooling of molten lava. While it lacks a crystalline structure, it is composed of mineral-like substances and is often classified as a mineraloid, a mineral-like substance that does not meet all the criteria of a mineral. f. Ruby: Yes, ruby is considered a mineral. It is a variety of the mineral corundum (Al₂O₃) and meets the geologic definition of a mineral as a naturally occurring inorganic solid with a definite chemical composition and a crystalline structure. g. Glacial ice: Glacial ice is not considered a mineral. Although ice itself is a mineral, the term "glacial ice" refers to a mixture of ice, snow, and air that forms glaciers. It is not a crystalline solid with a specific chemical composition but rather a combination of various materials. h. Amber: Yes, amber is considered a mineraloid. It is an organic substance derived from the fossilized resin of ancient trees. While it lacks a crystalline structure, it is composed of complex organic compounds and is often classified as a mineraloid. In summary, the items on the list that are considered minerals according to the geologic definition are: - Gold nugget - Quartz - Ruby The items that are not considered minerals are: - Seawater - Cubic zirconia - Glacial ice Obsidian and amber are classified as mineraloids, which are mineral-like substances that do not meet all the criteria of a mineral.