Ghost ships, crop circles, and soft gold: A GPS mystery in Shanghai

If you’re curious about the value of sand there is an awesome book named “The World in a Grain” which covers the use, history, and scarcity of sand.

https://www.penguinrandomhouse.com/books/537681/the-world-in...

The "soft gold" is sand:

> The reason they’re doing this has to do with the cargo the New Glory was carrying when it ran aground: plain, everyday sand.

> Chinese builders call it “soft gold.” Sand dredged from Yangtze River, which has the ideal consistency and composition for cement, helped fuel Shanghai’s construction boom in the 1980s and 1990s. By the turn of the millennium, reckless sand extraction had undermined bridges, trashed ecosystems, and caused long stretches of the riverbank to collapse. In 2000, Chinese authorities banned sand mining on the Yangtze completely.

Which is actually a non-renewable resource, and so for certain types, it can be quite valuable:

* https://www.bbc.com/future/article/20191108-why-the-world-is...

Could it simply be a spoofing device that spins? Say it broadcasts spoofed GPS location signals that travel along the circle say on 15* and the rest is jamming. Then different receivers would think they were in different locations as long as they were both not on the straight line to the antenna. It would also simulate the ship receiver believing it was traveling at seven knots when stationary.