Photoshop's default drop shadow is good enough to create a normal halo style drop shadow effect. But when it comes to casting perspective shadow it takes a little effort.
Lets create a cast shadow effect of the vase.
Using magic wand tool click on white area of the image. Press shift and click on white area inside the handle to include it in selection.
Press Shift+Ctrl+I to inverse the selection.
Press Ctrl+J twice to create duplicate layers of vase cutout. Fill the background layer with solid white color.
Select the vase layer right above the white background layer.
Press Ctrl+T. Right Click and select ditort. Adjust the nodes as shown.
Press enter to ok the changes. Click to enable lock transparent pixels from the layer palette.
Fill solid grey color in this layer. Again click to disable lock transparent pixels from the layer palette.
From filter menu select Blur>>Gaussian Blur. Apply settings as shown.
