The key difference between Epsom salt and rock salt is that Epsom salt mainly contains magnesium and sulfate ions, whereas rock salt mainly contains sodium and chloride ions.
Epsom salt and rock salt are two types of inorganic minerals. These salt compounds occur naturally in mineral deposits. Epsom salt is the solid magnesium sulfate that has the chemical formula MgSO4(H2O)7. Rock salt or halite is an inorganic mineral containing mainly sodium chloride.
CONTENTS
1. Overview and Key Difference
2. What is Epsom Salt
3. What is Rock Salt
4. Epsom Salt vs Rock Salt in Tabular Form
5. Summary – Epsom Salt vs Rock Salt
What is Epsom Salt?
Epsom salt is the solid magnesium sulfate that has the chemical formula MgSO4(H2O)7. Its mineralogical name is epsomite. This compound has been important as a bath salt since ancient times. It is also useful as a beauty product. This compound appears as colourless, tiny crystals, which resemble the appearance of table salt.
Figure 01: Epsom Salt
The name of this compound is derived from its source – the bitter saline spring in Epsom in Surrey. We use this compound both externally and internally. It is highly water-soluble. There are many benefits of Epsom salt, which include easing the stress and relaxing the body, relieving cramping and pain, improving muscle function, prevention artery hardening and blood clots, making insulin more effective, and relieving constipation.
What is Rock Salt?
Rock salt or halite is an inorganic mineral substance containing mainly sodium chloride. This is a naturally occurring mineral salt, and it occurs as isometric crystals. Typically, this substance is colourless or white, but there can be blue, purple, red, etc., colourations due to the presence of impurities. We can find this mineral naturally occurring in evaporite deposit minerals such as sulfate minerals, halide minerals, and borates.
Figure 02: Appearance of Rock Salt
The rock salt mainly contains NaCl (sodium chloride), and it has a cubic crystal system. The crystal class of this substance is hexoctahedral. The cleavage of rock salt is perfect in three directions, and it occurs in a cubic manner. The fracture of rock salt is conchoidal, and it is a brittle mineral substance. It has a vitreous lustre and the mineral streak colour is white. It appears to be transparent and is isotropic as well. This mineral is water-soluble due to its ionic nature.
There are different uses of rock salt, such as in cooking as a flavour enhancer, in curing food items like bacon and fish, in managing ice (as a de-icing agent), as a mineral fertilizer, etc.
What is the Difference Between Epsom Salt and Rock Salt?
Epsom salt and rock salt are two types of inorganic minerals. These salt compounds occur naturally in mineral deposits. Epsom salt is the solid magnesium sulfate that has the chemical formula MgSO4(H2O)7 while rock salt or halite is an inorganic mineral substance containing mainly sodium chloride. The key difference between Epsom salt and rock salt is that Epsom salt mainly contains magnesium and sulfate ions, whereas rock salt mainly contains sodium can chloride ions.
The following infographic lists the differences between Epsom salt and rock salt in tabular form for side by side comparison.
Summary – Epsom Salt vs Rock Salt
Epsom salt and rock salt are two types of inorganic minerals. The key difference between Epsom salt and rock salt is that Epsom salt mainly contains magnesium and sulfate ions, whereas rock salt mainly contains sodium can chloride ions.
Reference:
1. LaVolpe, Natalie “20 Surprising Uses for Epsom Salt.” Farmers’ Almanac, 20 Apr. 2021.
Image Courtesy:
1. “Magnesium sulfate” By Chemicalinterest at en.wikipedia – Own work (Public Domain) via Commons Wikimedia
2. “Halit (NaCl) – Kopalnia soli Wieliczka, Polska” By Lech Darski – Own work (CC BY-SA 4.0) via Commons Wikimedia