Five ingenious scientists start their epic journey on the other side of the world to hunt for gold. Kate Humble joins the team of modern day prospectors as they follow in the footsteps of the original gold pioneers on the rugged and unforgiving west coast of New Zealand's South Island.

To find gold they have to solve a series of seeming impossible challenges with only basic tools, simple materials and a few helpful household items like a bag of sugar and some old radios. The scientists’ brainpower, and muscle power, are tested to the limit as they battle with dense forest and fast flowing rivers in one of the wettest places on Earth, with over 5 metres of rain a year. The team's ultimate challenge is to make a souvenir from pure New Zealand gold.

Explore the science

The scientists begin by trying to collect gold from a river, building a home-made metal detector, and constructing a super accurate balance capable of weighing micro-grams of gold. The Rough Scientists have explained the science behind these challenges.

What is a carat? Discover the properties of gold and how to search for it.

Why does a metal detector make a noise when it passes over metal? Investigate the physics and gain the know-how to make one for yourself.

Is it possible to measure micro-grams? Find out how a balance works and whether it's easier to weigh light or heavy objects.

Diaries

How did the scientists cope with this week's challenges? Did Kathy struggle to measure micro-grams? Was this the first time Ellen and Mike B and Mike L had tried panning? Was Jonathan pleased with his metal detector? Read each of the Rough Scientists' personal diaries to find out what life was really like in New Zealand.

Forum

What did you think of the way the scientists tackled their challenges? Could you have come up with a better solution? Send in your comments and join the Open2 Forum. Mike Leahy and Jonathan Hare are on hand to answer your questions relating to this week's challenges.