Refractive Indices

706.5

1.74815

656.3

1.75063

643.8

1.75132

632.8

1.75197

589.3

1.75487

587.6

1.75500

546.1

1.75844

486.1

1.76506

480.0

1.76588

435.8

1.77295

404.7

1.77953

365.0

1.79081

Constants of Dispersion Formula

3.0182184

-1.538163310

2.152013710

6.460830310

-3.235574810

2.079159310

Relative Partial Dispersions  

0.3030

0.2526

0.2383

0.2362

0.5472

0.4856

-0.0024

-0.0068

Chemical Properties

Grade

1

3

1

3

ThermalProperties

682

710

636

663

60

70

 Mechanical Properties

784

12018

4655

0.291

Stress-Optical 
Coefficient

Coloration Code

41/31

Other Properties

4.51

Internal Transmittance

2400

2200

2000

1800

1600

1400

1200

1060

1000

950

900

850

800

700

0.999

0.998

650

0.999

0.997

600

0.998

0.996

550

0.998

0.996

500

0.996

0.993

480

0.995

0.990

460

0.994

0.988

440

0.986

0.973

420

0.978

0.956

400

0.958

0.917

390

0.939

0.882

380

0.910

0.828

370

0.87

0.76

360

0.81

0.66

350

0.73

0.53

340

0.63

0.40

330

0.52

0.27

320

0.40

0.16

310

 0.28

 0.08

300

 0.20

 0.04

290

 0.10

 0.01

280