14 16 18 20 22 24 26

0

20

40

60

80

100

4

32

Re

lative

Ab

so

rba

nce

1

Historical sample

250 300 350 4000

20

40

60

80

100

NH2

NH2

NH2

+

Cl-

Re

lative

Ab

un

da

nce

m/z

288

250 300 350 4000

20

40

60

80

100

NH2

NH2

NH2

+

CH3

CH3 CH3

Cl-

Re

lative

Ab

un

da

nce

m/z

250 300 350 4000

20

40

60

80

100

NH2

NH2

NH2

+

CH3

Cl-

4: New Fuchsin3: Magenta II

2: Rosaniline

330316

Re

lative

Ab

un

da

nce

m/z

3021: Pararosaniline

250 300 350 4000

20

40

60

80

100

NH2

NH2

NH2

+

CH3

CH3

Cl-

Re

lative

Ab

un

da

nce

m/z

Time (min)

1Rhodamine B

4Fuchsin compounds

1Indigo carmine

4Haematoxylum campechianum L.Logwood

16Isatis tinctoria L./Indigofera tinctoria L.and other

Indigo/woad

1Rhamnus treesBuckthorn berries

4Genista tinctoria L.Dyer’s broom

8Reseda luteola L.Weld

11Cotinus coggygria Scop.Young fustic

3Rubia tinctorum L.Madder

12Caesalpinia treesRedwood

19Dactylopius coccus Costa (most likely)Cochineal

No of objectsBiological sourceDye

300 400 5000

20

40

60

80

100

m/z

300 400 5000

20

40

60

80

100

m/z

300 400 5000

20

40

60

80

100

dcVIIdcIV

491491

Rela

tive A

bundance

m/z

dcII

10 12 14 16 18

0

10

20

30

dcVIIdcIV

CA

Re

lative

In

ten

sity

Time (min)

dcII

275

12 14 16 18 20 22

0

20

40

60

80

100

12 14 16 18 20 22

0

20

40

60

80

100

b. Treatment with TFA

5

43

1

2

Re

lative

Ab

so

rba

nce

Time (min)

5

76

76

Re

lative

Ab

so

rba

nce

a. Treatment with HCl

18 20 22 24 26 28

0

20

40

60

80

100

18 20 22 24 26 28

0

20

40

60

80

100

b. Standards mixture

Time (min)

7

6

54

3

2

1

Rela

tive

Absorb

ance

Rela

tive

Absorb

ance

7

6

5

4

321

a. Historical sample

6 8 10 12 14 16

0

20

40

60

80

100281

m/z

c. Logwood + HCl

Time (min)

6 8 10 12 14 16

0

20

40

60

80

100

6 8 10 12 14 16

0

20

40

60

80

100

b. Haematein + HCl

Re

lative

Ab

so

rba

nce

Re

lative

Ab

so

rba

nce

Re

lative

Ab

so

rba

nce

Haematein derivative

a. Historical sample + HCl

200 300 400 500 6000

20

40

60

80

100

275

221

453

Wavelength (nm)

Re

lative

Ab

so

rba

nce

200 300 400 500 6000

20

40

60

80

100

Re

lative

Ab

un

da

nce

331