Tin(II) chloride dihydrate is also three-coordinate, with one water coordinated on to the tin, and a second water coordinated to the first. The main part of the molecule stacks into double layers in the crystal lattice, with the "second" water sandwiched between the layers. Tin(II) chloride can dissolve in less than its own mass of water without apparent decomposition, but as the solution is diluted, hydrolysis occurs to form an insoluble basic salt: Therefore, if clear solutions of tin(II) chloride are to be used, it must be dissolved in hydrochloric acid (typically of the same or greater molarity as the stannous chloride)
Dartmoor tin-mining documentary evidence also relates: that there was a boom in tin production in the 13th century. The earliest written record of tin streaming comes from the 12th century. By the 15th century, the sources of stream tin were becoming scarce and since the demand for tin was as strong as ever, the direct working of lodes was considered viable despite the greater effort needed in both extraction and refining. "Beamworks" was the name given by the tinners to workings where the lode was followed by digging down from the surface, and the massive gullies that resulted remain prominent features of