IRIS BLUE (SUSANĪ)
First Technique:
The first technique is described in the sources Resāleh-ye Ḵošnevīsī (1120 A.H./1708 A.D.), and Resāleh Dar Bayān-e Rang Kardan-e Kāğaḏ (19th century) as follows:
کاغذی که نیل او بیشترک و سبز رنگ تر باشد و تیره بُوَد در شهاب اعلا به همان ترتیب کشیده و از آنجا در آب لیمون زده، در ظرف آب صاف شست و شوی داده، در سایه خشک نماید
Dye the paper in an indigo solution. For a deeper and greener shade, immerse the paper in a more concentrated indigo mixture for an extended period. Sequentially, dip the paper first in the first extract of safflower (šahāb-e aʿlā), then in lemon juice, and finally in water. Conclude the process by allowing the paper to dry in the shade.
Second Technique:
The second technique is described for iris (susanī) in Resāleh-ye Joharrieh (837 AH/1433 A.D and Resāleh dar Maʿrefat-e Kāḡaḏ-e Alvān (19th century) in the same manner. The recipe describes how to make iris (susanī) with mixture of yellow and blue along with other green shades of colours namely China jade green (chini) and tulip (laleh) in the same mixture which are lighter green comparing to iris (susani). This process allows for papers to absorb required dye with different concentration at different time periods. The more concentrated and longer time is referred to as iris (susanī) colour and the less concentrated dye with shorter time period is referred to lighter hues of green i.e. laleh and then chini accordingly:
ده مثقال آب زرد صافی بر سر آب کبود بیندازد، و اول حکم چینی کند، و دوم حکم لاله، و سیم سوسن. باید که مراعات بجای آورد، یعنی رنگ سوسن بر دهد. و دو رنگ دیگر صبر کند
Pour ten misqal of clear yellow extract into the blue dye. First, dye the papers to obtain the China green jade (chini) color, followed by the second dyeing for the tulip (laleh) color and the third for the iris (susanī) green. Ensure patience between each dyeing process, allowing the colors to develop[1].
Note: For China jade (chini) and tulip (laleh) refer to other shades of colour under blue to green shades.
[1] This process allows longer time to get susani colour and lesser time for the lighter hues of laleh and cini accordingly.
Experiment - First Technique:
Begin by making a deep, concentrated blue dye. Dip the paper into it and let it dry to achieve a dark blue indigo paper. Then dip the blue-dyed paper in the first extract of red safflower dye until you get the blue-green iris color paper. Subsequently, dip it in lemon juice and then clear water, followed by drying the paper in the shade.
Experiment - Second Technique:
Gradually add 20 ml of concentrated yellow safflower to blue indigo dye until you achieve the iris color shade. If more yellow safflower is needed to get the desired color, add more. Dip three papers into the mixture. Submerge the papers for different periods of time. First, remove the paper to obtain the China green jade (chini) color, followed by removing the second dyeing for the tulip (laleh) color, and the third for the iris (susanī) green. Ensure patience between each dyeing process, allowing the colors to develop.