Metal is all around us, sometimes shining, often matangaro (invisible). It is the tupua (magic) behind early photography and the secret to fertile volcanic soils. Without it, Piha Beach would leave your waewae (feet) a lot mā kē atu (cleaner).

Gunning for Waikato's riches

Metal roads connected remote parts of New Zealand.

How do you defeat hoariri (an enemy)? Often it means taking up arms. In the unsettled times of the 1860s, soldiers carried around pū (muskets) like the one shown. Governor Grey ordered his army to take up arms when he wanted to suppress the Kīngitanga (Māori monarchy) in the Waikato.

To move his hōia (soldiers) around easily, he built the Great South Road from Auckland to the Waikato. On arrival in the Waikato, his army grabbed King Pōtatau’s fertile whenua (land).

Super vegetables

The soil at Pukekohe, on Auckland's southern border, has a distinct red colour. It's caused by a high iron oxide content.

Market gardeners of Chinese heritage like 'The Fresh Grower' Allan Fong are still making use of this rich soil today. But in the 1860s one of the earliest Chinese families, the Ah Chees, started gardening in Carlaw Park, Newmarket. Almost a hundred years later, in 1958, they co-founded Foodtown in Ōtāhuhu - New Zealand’s first supermarket.

Treasure from the deep

Hiriwa (silver) and kōura (gold) are prized maitai (metals) that have attracted many adventurers to Auckland.

Think only pirates find sunken treasure on crusty old shipwrecks? Think again. Underwater explorer Kelly Tarlton and his mate Wade Doak found exactly that on the good kaipuke (ship) SS Elingamite during a ruku moana (diving) expedition in 1966.

The ship was taking a heap of coins to New Zealand, but ran aground near the Three Kings Islands and sank in 1902. Kelly Tarlton (1938–85) was also a marine conservationist. Have you visited the kauranga ika (aquarium) he built in Ōrākei?

The magnetic draw of the west coast beaches

Onepū mangu (black sand) gets its colour from high levels of iron-rich minerals.

Have you ever taken an autō (magnet) to Muriwai Beach on the west coast? Because of its iron content, the black sand jumps out and sticks to the magnet! You’ll find this black sand all the way from South Kaipara down Auckland’s west coast.

It's hard to believe, but this sand was once toka puia (volcanic rock) in the central North Island and the Taranaki region, hundreds of kilometres south of Auckland.

For thousands of years it has been washed down the Waikato River and up the coast from the south, finally landing on Auckland's beaches.

Check out the Museum's oldest photo

Prized for its cool beauty, silver was once essential to photography.

These days you just whip out your waea (phone) to take a kapomata (selfie). But in the early days, photographers used the very complicated daguerreotype (sounds like dag-air-o-type) process, which requires light-sensitive silver pereti (plates) and all sorts of dangerous matū (chemicals).

Photography developed around the same time as colonial Auckland, so there are many photos from this era. This photograph is of Ngāi te Rangi missionary Hēnare Taratoa at his mārena (wedding) to Emily Te Rua at St John’s College in Meadowbank.