In the remarks column of the South Red Agate Appraisal Certificate, six asterisks usually indicate special marks or special instructions. These asterisks may indicate the following:

1. Precious degree: Six asterisks may indicate that the southern agate is extremely precious, and it is a very rare and precious gem. This may be due to its rare origin, special color or unique grain.

2. Purity and quality: The asterisk may indicate that South Red Agate has extremely high standards in purity and quality. This may mean that it has no obvious flaws, uniform and full color, good luster and transparency.

3. Rare varieties: There are many varieties of south red agate, some of which may be very rare. Six asterisks may indicate that this is a particularly rare species, such as red, red yellow or red-black southern red agate.

4. Origin: The asterisk may also indicate the origin or specific origin of South Red Agate. Some southern agate producing areas are specially marked because of their unique geological conditions, producing high-quality gems.

It should be noted that the specific labeling and interpretation of the appraisal certificate of South Red Agate may be different due to the different appraisal institutions, experts and certificate locations. Therefore, if you want to know the exact meaning of the six asterisks, you'd better consult an appraisal agency or a certificate issuing agency for a more detailed explanation.