Engraving slate with a laser requires specific settings to achieve the best results. Typically, a CO2 laser is used for this purpose. Recommended settings include:

• Power: Set the laser power between 30% to 50%. This balance helps to effectively engrave the slate without causing excessive burning or chipping.
• Speed: Use a speed of around 200 to 300 mm/s. Slower speeds can lead to deeper engravings, while faster speeds will result in lighter marks.
• Frequency: For most slate types, a frequency setting of 500 to 1000 Hz works well. Higher frequencies can help create finer details.
• Passes: Depending on the thickness and type of slate, 1 to 3 passes may be needed. Test with a single pass first and adjust as necessary.
• Focus: Ensure the laser is properly focused for optimal engraving depth and detail.

Before starting a project, it is advisable to conduct a test run on a small piece of slate to fine-tune your settings for the specific material.