To fix a broken Bronze Armani marble step, you can follow these steps:

1. Assess the damage: Examine the extent of the breakage, including any loose or fragmented pieces. Determine if it is a small chip, a crack, or a more significant break.

2. Gather the necessary materials: You will need epoxy adhesive, a putty knife, a small paintbrush, fine-grit sandpaper, a damp cloth, and a marble sealer.

3. Clean the area: Use a damp cloth to thoroughly clean the broken area and remove any loose debris or dust particles. Allow it to dry completely before proceeding.

4. Prepare the epoxy adhesive: Follow the manufacturers instructions to prepare the epoxy adhesive. Typically, you will need to mix the resin and hardener components as per the given ratio and stir them well.

5. Apply the epoxy adhesive: Using a small paintbrush or a putty knife, apply the epoxy adhesive to the broken edges of the marble step. Make sure to apply a thin and even layer, covering the entire surface area that needs to be repaired.

6. Realign the broken pieces: Carefully realign the broken pieces of the marble step and gently press them together. Hold them in place for a few minutes until the epoxy adhesive starts to set.

7. Clean up excess adhesive: Utilize a damp cloth or a cotton swab to remove any excess epoxy adhesive that may have oozed out from the edges. Ensure the surface is smooth and clean.

8. Allow curing time: Follow the epoxy adhesive manufacturers instructions for the recommended curing time. This period can vary depending on the specific product used.

9. Sand and polish: Once the epoxy has fully cured, use fine-grit sandpaper to smooth out any rough or uneven edges. Gently sand the repaired area until it matches the level and texture of the rest of the step. Be cautious not to oversand or damage the surrounding surface.

10. Apply marble sealer: Finally, apply a marble sealer to the repaired area. Follow the manufacturers instructions for the application process, and ensure the sealer is evenly distributed across the entire step. This will help protect and maintain the repaired section over time.

If the damage is extensive or if you are unsure about handling the repair on your own, it may be best to consult a professional stone repair specialist who can provide expert assistance in fixing your broken Bronze Armani marble step.