18k hgf would stand for 18k heavy gold filled ( not solid gold )
Mercuryfluoride
The formula given is for mercury (I) fluoride, also known as mercurous fluoride.
The empirical formula for Hg₂F₂ is HgF. This is because the empirical formula represents the simplest whole-number ratio of atoms in a compound.
It could mean 18 karat "hollow gold filled". I'm not familiar with a manufacturer's hallmark that is "HGF".
HgF
Heavy gold filled
"14k HGF" typically refers to a type of gold jewelry or item that is made from 14 karat gold and may include the initials "HGF," which could stand for a brand, designer, or manufacturer. The "14k" indicates that the gold is 58.3% pure, with the remaining 41.7% being other metals, which is common in jewelry for durability and color. If "HGF" has a specific context or meaning beyond that, it may require additional information to clarify.
It means 18kt gold electroplated.
It is worth nothing at all. HGE refers to heavy gold electroplated. Though 18KT refers to 18 karat gold or 75 percentage gold, 18KT HGE is worth nothing.
18kt refers to a piece of jewelry that is made of 75% pure gold, with the remaining 25% composed of other metals like copper, silver, or zinc. The "kt" stands for karat, a unit of measurement used to indicate the purity of gold in a piece of jewelry. 18kt gold is a popular choice for fine jewelry due to its balance of durability and luxury.
An angle whose measure is 20 degrees!