Measured properties

20 g Imported bentonite

20 g Local bentonite

20 g local bentonite + 4 g Na₂CO₃ + 10 g cassava starch

25 g local bentonite + 5 g Na₂CO₃ + 10 g cassava starch

30 g local bentonite + 6 g Na₂CO₃ + 10 g cassava starch

35 g local bentonite + 7 g Na₂CO₃ + 10 g cassava starch

40 g local bentonite + 8 g Na₂CO₃ + 10 g cassava starch

pH

10.21

7.80

10.50

10.55

10.60

10.70

10.90

Specific gravity

1.025

1.04

1.06

1.06

1.075

1.092

1.118

Mud density (ppg)

8.55

8.68

8.84

8.84

8.97

9.11

9.33

Viscosity (cp), 600 rpm

40.00

20.70

26.50

32.50

34.00

36.00

38.10

Viscosity (cp), 300 rpm

28.00

17.00

22.60

27.90

29.80

31.00

32.60

Plastic viscosity (cp)

12.00

3.70

3.90

4.60

4.20

5.00

5.50

Apparent viscosity (cp)

20.00

10.35

13.25

16.25

17.00

18.00

19.05

Yield point (lb/100 ft²)

16.00

13.33

18.70

23.30

25.60

26.00

27.10

Fluid loss (ml) at 30 min

11.00

52.50

29.00

26.50

19.00

15.70

12.60