Sinter (on the Lions-Head)
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Go to the coordinates listed, and you will see the following below you (this is NOT the sinter!):
If you now look towards the west from your current position, you can see the sinter deposits on two of the rocks. These are only 1-2 meters away from you. Sinter is clearly distinguishable from the surface of the rock formation.
Here are the questions:
1. Describe the surface, hardness, shape and size of the sinter.
2. Describe the shape that the sinter forms (e.g., small spheres, stalactites, etc.).
3. Estimate what percentage of the rocks in front of you are covered with sinter.
4. Take a picture of yourself (make sure it doesn't spoil anything!) with Lentas village in the background. You can post it on the log or send it to us along with your answers.
What is sinter?
Sinter is rock that is created by deposits of minerals. There are different forms in which these deposits can be created. Both in composition and in appearance. Basically, the sinter is formed by separating out minerals dissolved in water. This is also called crystallization. This can happen in different locations. In bodies of water, water pipes, water containers and in a humid environment. In the process, crust-like coatings are formed. The crusts can be of different sizes and shapes. In caves this effect also leads to the formation of stalactites. In order for the sinter to form, the minerals must be dissolved. Depending on the surrounding conditions, various options can be considered. Salty sea water can play a role. This can loosen limestone and lead to deposits. In other cases, salts are dissolved in the subsurface and wash out minerals.
Naturally occurring mineral deposits of relatively pure composition include: calcareous sinter, which consists mainly of calcium carbonate (such as travertine, calcareous tuff, cave pearls, and pisolite); siliceous sinter, composed of cryptocrystalline silica or opal, which can deposit at hot springs (e.g., geysers) and is sometimes called geyserite; and sulfurous sinter, primarily various sulfides and sulfates, often resulting from volcanic activity. Mineral formations such as quartz veins in other rocks, agate, and geodes can be considered a special case. Salt deposits (evaporites), especially rock salt (halite), are strictly speaking also sinter, but this term is not commonly used for them. A concretion, a rock formed by precipitation, such as bog iron ore, can take on forms resembling sinter.
The geology of Crete has a lot of different typs of rocks to offer. You can learn a lot about the history of the earth here.
Sources: Wikipedia, own observations