Iron
Original title: Ferro
Account of iron minerals in the Madeira archipelago, abundant but not worth mining, and their role in rock weathering and soil colouring.
Large quantities of this mineral are found in the archipelago, but in compounds not worth mining. Where it occurs in higher concentrations, it is only in tiny veins, such as the beautiful plates of specular iron in the cliff overlooking the Cais da Ponta do Sol (‘point of the sun’), and in the inner linings of lava tubes, as in the caves of Cavalum, in Machico, and the cave of Cardais (‘thistle patches’), in São Vicente.
It is owing to iron salts that most of the rocks on our slopes break down. This is how new soils (poios) are prepared: the rocks are left to crumble under the action of natural agents, and the soil is then retained in small cultivation terraces.
Iron gives the greyish-brown colour to the coatings of basalt blocks and the red colour to the soils known as massapês (red clayey soil), and it also produces the laterites that streak the rocks, especially along the coast, sandwiched between two basalt layers.
It is found in granular form among the tuffs at Canhas, in cellular form at Madalena do Mar (‘Magdalene by the sea’), and in lamellar form over clays at Sant’Ana and São Jorge, looking like scrap iron, and dissolved in the water of some springs, such as the Jamboto spring in Santo António. S.
In this article
Place
Places mentioned · 08
- Cais da Ponta do Sol
Ponta do Sol. Rock above it shows specular iron plates.
The Cais da Ponta do Sol is the landing quay of Ponta do Sol, begun on 8 May 1848 and apparently finished in 1850 at the municipal council's expense. It is architecturally notable and gives direct access to the town centre, though landing there was sometimes harder than at Lugar de Baixo. The rock above it shows plates of specular iron.
- Canhas
Ponta do Sol. Granular iron occurs among tuffs here.
Canhas is a parish in the municipality of Ponta do Sol on Madeira's south coast, named after the Canha family and created in 1577, first installed at the chapel of São Tiago. The Elucidário records its church and chapels, local dress and speech, industries and localities such as Outeiro and Carvalhal e Carreira, its irrigation by a small private levada, and the sesmaria of Martim Afonso da Cunha.
- Fonte do Jamboto
Funchal. Spring whose water contains dissolved iron.
Spring whose water contains dissolved iron.
- Madalena do Mar
Ponta do Sol. Cellular iron occurs here.
Madalena do Mar is a parish on the south-west coast of Madeira, in the municipality of Ponta do Sol, founded on the estate of the legendary Henrique Alemão and made an independent parish in 1582. The Elucidário records its chapels, sugar and banana farming, its capitania-mor, damage in the 1876 floods and the 1939 flood of the Ribeira da Madalena, and it was the birthplace of António Policarpo dos Passos Sousa.
- Santana
Lamellar iron over clays occurs here.
Santana is a parish on Madeira's north coast, praised as the most picturesque of the north. It was created from São Jorge in the 16th century, and the entry covers its settlement, parish priests, church, localities and population.
- São Jorge
Santana. Lamellar iron over clays occurs here.
North-coast parish that was an original parish of Santana municipality and gives its name to the northern archpriest district. It is known for plant-fossil and lignite deposits studied by Heer and Bunbury, and for a 17th-century landslide. The Elucidário also describes its islet, headland, quay and stream.