Argyle historically applied its proprietary colour naming and intensity numbering to pink and violet stones before submitting them to GIA. https://www.jennybay.com.au/argyle-pink-diamond/?srsltid=AfmBOoq7g-v2gNgKlfN9d6W8wvJYQ-Ck_CAjwqtQY-xSkSr0inVZHz5y