Which of the following is NOT a mineraloid?Group of answer choicesAmberIcethe crystals that make up tooth enamelOpal

To identify which of the options is NOT a mineraloid, we first need to clarify the definitions of each option.

1. Amber: A fossilized tree resin, commonly considered a mineraloid due to its organic origin and lack of a crystalline structure.

2. Ice: While ice is a solid form of water, it has a regular internal structure and is therefore classified as a mineral (not a mineraloid) when it forms in crystalline structure.

3. The crystals that make up tooth enamel: Tooth enamel is primarily made up of hydroxyapatite, which is a crystalline mineral. Thus, it is also classified as a mineral.

4. Opal: Opal is a mineraloid because it does not possess a crystalline structure despite being composed of silica.

Conclusion

Based on this analysis, the correct answer to the question, "Which of the following is NOT a mineraloid?" is Ice, as it typically forms a crystalline structure and is classified as a mineral.