If you want to lay a paver walkway, you will have to decide whether to use stone dust or sand for this job. Either can be very useful, although some professionals will insist that one is better than the other. Both sand and stone dust act as an underlay for the pavers, and while both can be used, there are some reasons why people might prefer sand.
Stone dust is often used in areas where there is a lot of underground water, as it will absorb less water than sand. Stone dust is also cheaper than sand, and is more environmentally friendly, making it a suitable base for your paver walkway if you are concerned about any of these issues.
The real downside to stone dust is that it can be affected by frost. Ground frost will swell up water below the dust, which can then force up the patio. You should also consider that stone dust has a higher pH than the ground, which may cause the pavers to deteriorate over time.
Sand is a more reliable substance for your pathways, as it will compact easily, and can also move around if the frost causes ground water to increase in size. It also is a neutral pH which will not affect the pavers.