
Ghost ships, crop circles, and soft gold: A GPS mystery in Shanghai - DyslexicAtheist
https://www.technologyreview.com/s/614689/ghost-ships-crop-circles-and-soft-gold-a-gps-mystery-in-shanghai/
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etxm
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...](https://www.penguinrandomhouse.com/books/537681/the-world-in-a-grain-
by-vince-beiser/)

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throw0101a
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...](https://www.bbc.com/future/article/20191108-why-the-world-is-running-out-of-sand)

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mzs
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.

