Solid form of (−)-Ambrox formed by a bioconversion of homofarnesol in the presence of a biocatalyst

A method of preparing a solid form of (−)-Ambrox of the formula (I)

• wherein, said solid form is characterized by at least one of the following characteristics:
• it exhibits an x-ray diffraction pattern having at least one of the following peaks at diffraction angles 2 theta of 15.6, 16.2, 16.7, 17.0, 17.4, 18.3 +/−0.2°;
• it comprises elongate crystals having an average diameter of at least 10 to 400 microns measured by laser granulometry;
• it comprises elongate crystals having a length along their longest dimension of greater than 100 micron;
• and/or
• it has an L* value of 90 or more;
• an a* value of less than 1 and greater the −1;
• and a b* value, which is less than 8, wherein L*, a* and b* values represent CIELAB L*a*b* chromaticity coordinates,
• wherein the solid form of (−)-Ambrox is formed by a bioconversion process, said method comprising the steps of:
• I) forming crystalline (−)-Ambrox in a bioconversion medium by means of a biocatalytic process;
• and
• II) separating the crystalline (−)-Ambrox from the bioconversion medium.