  We present the results of magnetic measurements on Nd6Co(1.67)Si3, a compound
recently reported to crystallize in a hexagonal structure (space group P6_3/m)
and to undergo long range magnetic ordering below 84 K. The results reveal that
the magnetism of this compound is quite complex with additional magnetic
anomalies near 50 and 20 K. There are qualitative changes in the isothermal
magnetization behavior with the variation of temperature. Notably, there is a
field-induced spin reorientation as the temperature is lowered below 20 K. A
finding we stress is that this transition is discontinuous for 1.8K in the
virgin curve, but the first order character appears only after a field-cycling
for a narrow higher temperature range near 5 K. Thus, this compound serves as
an example for the stabilisation of first-order transition induced by
magnetic-field-cycling. The issues of 'Phase co-existence' and 'meta-stability'
after a field-cycling at low temperatures in this compound are also addressed.
