This EarthCache takes you to  14-22 Lands Lane, Leeds. We are here to examine the cladding of the building. 

 This cladding is a type of rock known as Sicilian Pearl (Perlato di Sicilia), which is a polished limestone from Sicily in Italy.

So what is limestone?

Limestone is a sedimentary rock.

Sedimentary rocks are types of rock  that are formed by the deposition and subsequent cementation of that material at the earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic  particles to settle in place. The particles that form a sedimentary rock by accumulating are called sediment. Before being deposited, the sediment was formed by weathering and erosion  from the source area, and then transported to the place of deposition by water, or wind.Sedimentation may also occur as minerals precipitate from water solution or shells of aquatic creatures settle out of suspension.

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate. Most limestone is composed of skeletal fragments of marine organisms such as coral, crinoids and molluscs.

There are already EarthCaches  in the town which deal with limestone, so how is this location different from the others?

STYLOLITES

If you look at the limestone panels, you will notice some irregular linear features which cross some of them, these are known as Stylolites. We are here to learn about stylolites. If you look at the blocks, you will notice some irregular lines crossing them both, these are stylolites. 

Stylolites form after lithification of sediments, which is  a diagenetic process. Lithification is the process of sediment forming stone, this happens due to pressure, and during this process, fluid contained in the sediment is gradually expelled. A diagenetic process, is when physical and chemical changes in sediment occur. Pressure during the lithification process  can cause stylolites to form. 

This being an EarthCache, in order to log it, I ask that you answer some questions. Please send them to me, and do not include them in your log. You can send them to me by using the message facility or email, both of which can be found by looking at my profile.

The best place to look at the stylolites are in the panels above the following two features;

1. Please describe the stylolites in terms of shape, length , diameter, and direction that they travel through the block.

2. Using  the above information please tell me what type of stylolite you can find.

3. What colour are the stylolites?